Help with diagnosing my Terminator X
Thread Starter
Joined: Apr 2006
Posts: 3,894
Likes: 1,139
From: Grand Rapids, Michigan
Help with diagnosing my Terminator X I recently installed a Terminator X EFI on my '98 Firebird Formula that's also running a piggyback setup with the factory PCM. Engine is an '06 turbo LH6, 24x/1x with a front mounted cam sensor. I've had some help with getting it tuned, but I've had a few problems pop up that I can't figure out. The first one is, we were street tuning it and out of nowhere it started to run rough. Diagnostic LED #7 was lit up red, cam sensor sync. So I bought a new cam sensor ( the original was the high mileage one from the donor engine )and it seemed to fix it. Was really pulling hard finally. Then it began to run rough again after a few hard pulls. This time both the cam & crank sensor sync popped up red. This only seems to happen when trying full throttle pulls, part throttle it doesn't seem to bother it any. Always seems to happen when it goes heavy into boost. Checked all grounds and harnesses, everything seems fine. What should I be looking for here? Could any of the safeties cause this to occur?
Second problem popped up after trying to figure out if the second fuel pump was working. I have a Racetronix twin 340 in-tank setup. It comes with a double pump hotwire harness that I have wired directly to the alternator. See here: https://www.racetronix.biz/p/udp-hd-...mp280/udph-005. Both pumps have ground switched relays out back. In a factory configuration using the factory PCM, each pump has a connector with a jumper wire so they both switch on at the same time. I didn't want that, so I used the Holley's green fuel pump wire and tied that into my integration harness's fuel pump request wire. This sends the request through the factory relay/fuse setup first, and then back to the relay in the rear of the car. On this pump, I left the jumper wire in place, as it allows the factory computer to control the pump as normal. Prior to testing to see if the second pump would turn on, the first pump worked fine. The second pump uses a ground side switched output from the Terminator X that's supposed to turn on at 2 psi boost and above 3000 RPM. We did some testing and found 61 Ohms resistance to ground when the pump was commanded on, which didn't sound right. Either way, my main problem occurred when I disconnected the output from the Holley and instead replaced it with the jumper that comes in the Racetronix kit. I meant to disconnect it after testing, but I drove the car for a few minutes with it. I figured that out, and reconnected everything as it was. However, every time the car goes into boost now, the fuel pump shuts right off. Like the green fuel pump output wire is shutting off the pump, nothing else makes sense. As soon as it's out of boost, fuel pressure goes back to normal. Every time it hits boost, instantly shuts off. Anyone have any idea what I should look for?
I posted this up on the Holley forum as well, and it was suggested to do a firmware update, so I'll make a go of that - In the meantime I just wanted to see if anyone has ran across either of these issues or knows what could cause them.
Second problem popped up after trying to figure out if the second fuel pump was working. I have a Racetronix twin 340 in-tank setup. It comes with a double pump hotwire harness that I have wired directly to the alternator. See here: https://www.racetronix.biz/p/udp-hd-...mp280/udph-005. Both pumps have ground switched relays out back. In a factory configuration using the factory PCM, each pump has a connector with a jumper wire so they both switch on at the same time. I didn't want that, so I used the Holley's green fuel pump wire and tied that into my integration harness's fuel pump request wire. This sends the request through the factory relay/fuse setup first, and then back to the relay in the rear of the car. On this pump, I left the jumper wire in place, as it allows the factory computer to control the pump as normal. Prior to testing to see if the second pump would turn on, the first pump worked fine. The second pump uses a ground side switched output from the Terminator X that's supposed to turn on at 2 psi boost and above 3000 RPM. We did some testing and found 61 Ohms resistance to ground when the pump was commanded on, which didn't sound right. Either way, my main problem occurred when I disconnected the output from the Holley and instead replaced it with the jumper that comes in the Racetronix kit. I meant to disconnect it after testing, but I drove the car for a few minutes with it. I figured that out, and reconnected everything as it was. However, every time the car goes into boost now, the fuel pump shuts right off. Like the green fuel pump output wire is shutting off the pump, nothing else makes sense. As soon as it's out of boost, fuel pressure goes back to normal. Every time it hits boost, instantly shuts off. Anyone have any idea what I should look for?
I posted this up on the Holley forum as well, and it was suggested to do a firmware update, so I'll make a go of that - In the meantime I just wanted to see if anyone has ran across either of these issues or knows what could cause them.
I recently installed a Terminator X EFI on my '98 Firebird Formula that's also running a piggyback setup with the factory PCM. Engine is an '06 turbo LH6, 24x/1x with a front mounted cam sensor. I've had some help with getting it tuned, but I've had a few problems pop up that I can't figure out. The first one is, we were street tuning it and out of nowhere it started to run rough. Diagnostic LED #7 was lit up red, cam sensor sync. So I bought a new cam sensor ( the original was the high mileage one from the donor engine )and it seemed to fix it. Was really pulling hard finally. Then it began to run rough again after a few hard pulls. This time both the cam & crank sensor sync popped up red. This only seems to happen when trying full throttle pulls, part throttle it doesn't seem to bother it any. Always seems to happen when it goes heavy into boost. Checked all grounds and harnesses, everything seems fine. What should I be looking for here? Could any of the safeties cause this to occur?
Second problem popped up after trying to figure out if the second fuel pump was working. I have a Racetronix twin 340 in-tank setup. It comes with a double pump hotwire harness that I have wired directly to the alternator. See here: https://www.racetronix.biz/p/udp-hd-...mp280/udph-005. Both pumps have ground switched relays out back. In a factory configuration using the factory PCM, each pump has a connector with a jumper wire so they both switch on at the same time. I didn't want that, so I used the Holley's green fuel pump wire and tied that into my integration harness's fuel pump request wire. This sends the request through the factory relay/fuse setup first, and then back to the relay in the rear of the car. On this pump, I left the jumper wire in place, as it allows the factory computer to control the pump as normal. Prior to testing to see if the second pump would turn on, the first pump worked fine. The second pump uses a ground side switched output from the Terminator X that's supposed to turn on at 2 psi boost and above 3000 RPM. We did some testing and found 61 Ohms resistance to ground when the pump was commanded on, which didn't sound right. Either way, my main problem occurred when I disconnected the output from the Holley and instead replaced it with the jumper that comes in the Racetronix kit. I meant to disconnect it after testing, but I drove the car for a few minutes with it. I figured that out, and reconnected everything as it was. However, every time the car goes into boost now, the fuel pump shuts right off. Like the green fuel pump output wire is shutting off the pump, nothing else makes sense. As soon as it's out of boost, fuel pressure goes back to normal. Every time it hits boost, instantly shuts off. Anyone have any idea what I should look for?
I posted this up on the Holley forum as well, and it was suggested to do a firmware update, so I'll make a go of that - In the meantime I just wanted to see if anyone has ran across either of these issues or knows what could cause them.
Second problem popped up after trying to figure out if the second fuel pump was working. I have a Racetronix twin 340 in-tank setup. It comes with a double pump hotwire harness that I have wired directly to the alternator. See here: https://www.racetronix.biz/p/udp-hd-...mp280/udph-005. Both pumps have ground switched relays out back. In a factory configuration using the factory PCM, each pump has a connector with a jumper wire so they both switch on at the same time. I didn't want that, so I used the Holley's green fuel pump wire and tied that into my integration harness's fuel pump request wire. This sends the request through the factory relay/fuse setup first, and then back to the relay in the rear of the car. On this pump, I left the jumper wire in place, as it allows the factory computer to control the pump as normal. Prior to testing to see if the second pump would turn on, the first pump worked fine. The second pump uses a ground side switched output from the Terminator X that's supposed to turn on at 2 psi boost and above 3000 RPM. We did some testing and found 61 Ohms resistance to ground when the pump was commanded on, which didn't sound right. Either way, my main problem occurred when I disconnected the output from the Holley and instead replaced it with the jumper that comes in the Racetronix kit. I meant to disconnect it after testing, but I drove the car for a few minutes with it. I figured that out, and reconnected everything as it was. However, every time the car goes into boost now, the fuel pump shuts right off. Like the green fuel pump output wire is shutting off the pump, nothing else makes sense. As soon as it's out of boost, fuel pressure goes back to normal. Every time it hits boost, instantly shuts off. Anyone have any idea what I should look for?
I posted this up on the Holley forum as well, and it was suggested to do a firmware update, so I'll make a go of that - In the meantime I just wanted to see if anyone has ran across either of these issues or knows what could cause them.
That said I attempted to use the same harness on my car going thru the factory relay and it flat out didn't work. For whatever reason I couldn't get power to the pumps using that harness. I was diagnosing it for like 3 days along side of talking to Racetronix and after all of that they still said it was something I was overlooking. I pulled it out cut up the harness and wired the pumps up and haven't had an issue since. Good luck.
Last edited by 91 Z28; Aug 24, 2024 at 01:11 PM.
Thread Starter
Joined: Apr 2006
Posts: 3,894
Likes: 1,139
From: Grand Rapids, Michigan
The way it's wired in, the green Terminator X pump trigger wire is connected to my integration harness, which then uses the factory relay to turn on pump #1. Pump #2 is configured using one of the Terminator X outputs, and is supposed to turn on over 3000 RPM and 2 lbs. of boost. Pump #2 isn't even needed yet, though, as I'm just running on 93 octane and on my 7 lb. wastegate spring. Aside from cutting off under boost, pump #1 works perfectly fine. I am going to have to pull the relay for pump #1 to test if pump #2 is working, though. I can't tell one pump running over two when they're in the tank side by side.
The way it's wired in, the green Terminator X pump trigger wire is connected to my integration harness, which then uses the factory relay to turn on pump #1. Pump #2 is configured using one of the Terminator X outputs, and is supposed to turn on over 3000 RPM and 2 lbs. of boost. Pump #2 isn't even needed yet, though, as I'm just running on 93 octane and on my 7 lb. wastegate spring. Aside from cutting off under boost, pump #1 works perfectly fine. I am going to have to pull the relay for pump #1 to test if pump #2 is working, though. I can't tell one pump running over two when they're in the tank side by side.
Edit: Yes it does have that function. No need to pull any relays just hook up your laptop, key on and hit the output test button at the top. It'll show all your outputs and you can turn each one on from there
Thread Starter
Joined: Apr 2006
Posts: 3,894
Likes: 1,139
From: Grand Rapids, Michigan
Copied this from a post I made on the Holley forum, just to get more eyes on it. @91 Z28 , looking at my wiring explanation below, do you see anything wrong with how I wired it?
I did some diagnostics on the secondary fuel pump not turning on, and I don't know what is causing it yet. I verified that both pumps function correctly by switching which pump is the primary and which is secondary. I did an output test for the secondary pump, which is on pin B10, and it didn't turn on. I hooked my volt meter to the output and set it to ohms, and when I triggered the output, it was reading 40-60 ohms. I'm wondering if I have the secondary pump wired incorrectly? Here is a pic of where it gets tied into the double pump harness: https://www.racetronix.com/product/F...PH-005-1-L.jpg I left one of those looped terminals in, so the factory relay turns on the pump. That part works fine, and is triggered by the green fuel pump output wire on the Holley.
If you look at the pic, there's a black ground wire on one side of the terminal, and a red (or blue) wire on the other side of the terminal. The black ground wire is grounded to a stud on the engine adjacent to the alternator. The red wire goes to a relay for pump 1, the blue goes to a relay for pump 2. I used the output on B10 ( Grey w/ black stripe ) and made a terminal so it plugs into the double pump harness and connects to the blue wire. The opposite cavity I left empty, as I assumed it was no longer needed. My sensor ground from my Terminator X is grounded to my unibody under my passenger side kick panel. I ground the paint to bare metal before screwing it in, so I know it's making a good ground. In the rear of the car where the dual pump harness relays are located, there's another ground which I also attached to the unibody. There is also this intermediate harness that plugs into my stock '98 wiring: https://cdn.racetronix.biz/mmrtx/ima...pg?w=800&h=800 It has a ground that bolts to a stud I installed on top of the sender. 3 wires come out of the harness and go into the factory bulkhead under the car. Grey is fuel pump command, purple and black are for the gas gauge ( which doesn't work, but that's another problem ). The output is functioning correctly from what I can see, but is the 40-60 ohm reading plausible? When I have the connector plugged in and command the output on, there's no reaction from the pump. I'm at a loss here, wiring is not my specialty.
I did some diagnostics on the secondary fuel pump not turning on, and I don't know what is causing it yet. I verified that both pumps function correctly by switching which pump is the primary and which is secondary. I did an output test for the secondary pump, which is on pin B10, and it didn't turn on. I hooked my volt meter to the output and set it to ohms, and when I triggered the output, it was reading 40-60 ohms. I'm wondering if I have the secondary pump wired incorrectly? Here is a pic of where it gets tied into the double pump harness: https://www.racetronix.com/product/F...PH-005-1-L.jpg I left one of those looped terminals in, so the factory relay turns on the pump. That part works fine, and is triggered by the green fuel pump output wire on the Holley.
If you look at the pic, there's a black ground wire on one side of the terminal, and a red (or blue) wire on the other side of the terminal. The black ground wire is grounded to a stud on the engine adjacent to the alternator. The red wire goes to a relay for pump 1, the blue goes to a relay for pump 2. I used the output on B10 ( Grey w/ black stripe ) and made a terminal so it plugs into the double pump harness and connects to the blue wire. The opposite cavity I left empty, as I assumed it was no longer needed. My sensor ground from my Terminator X is grounded to my unibody under my passenger side kick panel. I ground the paint to bare metal before screwing it in, so I know it's making a good ground. In the rear of the car where the dual pump harness relays are located, there's another ground which I also attached to the unibody. There is also this intermediate harness that plugs into my stock '98 wiring: https://cdn.racetronix.biz/mmrtx/ima...pg?w=800&h=800 It has a ground that bolts to a stud I installed on top of the sender. 3 wires come out of the harness and go into the factory bulkhead under the car. Grey is fuel pump command, purple and black are for the gas gauge ( which doesn't work, but that's another problem ). The output is functioning correctly from what I can see, but is the 40-60 ohm reading plausible? When I have the connector plugged in and command the output on, there's no reaction from the pump. I'm at a loss here, wiring is not my specialty.
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Verdad Gallardo Copied this from a post I made on the Holley forum, just to get more eyes on it. @91 Z28 , looking at my wiring explanation below, do you see anything wrong with how I wired it?
I did some diagnostics on the secondary fuel pump not turning on, and I don't know what is causing it yet. I verified that both pumps function correctly by switching which pump is the primary and which is secondary. I did an output test for the secondary pump, which is on pin B10, and it didn't turn on. I hooked my volt meter to the output and set it to ohms, and when I triggered the output, it was reading 40-60 ohms. I'm wondering if I have the secondary pump wired incorrectly? Here is a pic of where it gets tied into the double pump harness: https://www.racetronix.com/product/F...PH-005-1-L.jpg I left one of those looped terminals in, so the factory relay turns on the pump. That part works fine, and is triggered by the green fuel pump output wire on the Holley.
If you look at the pic, there's a black ground wire on one side of the terminal, and a red (or blue) wire on the other side of the terminal. The black ground wire is grounded to a stud on the engine adjacent to the alternator. The red wire goes to a relay for pump 1, the blue goes to a relay for pump 2. I used the output on B10 ( Grey w/ black stripe ) and made a terminal so it plugs into the double pump harness and connects to the blue wire. The opposite cavity I left empty, as I assumed it was no longer needed. My sensor ground from my Terminator X is grounded to my unibody under my passenger side kick panel. I ground the paint to bare metal before screwing it in, so I know it's making a good ground. In the rear of the car where the dual pump harness relays are located, there's another ground which I also attached to the unibody. There is also this intermediate harness that plugs into my stock '98 wiring: https://cdn.racetronix.biz/mmrtx/ima...pg?w=800&h=800 It has a ground that bolts to a stud I installed on top of the sender. 3 wires come out of the harness and go into the factory bulkhead under the car. Grey is fuel pump command, purple and black are for the gas gauge ( which doesn't work, but that's another problem ). The output is functioning correctly from what I can see, but is the 40-60 ohm reading plausible? When I have the connector plugged in and command the output on, there's no reaction from the pump. I'm at a loss here, wiring is not my specialty.
I did some diagnostics on the secondary fuel pump not turning on, and I don't know what is causing it yet. I verified that both pumps function correctly by switching which pump is the primary and which is secondary. I did an output test for the secondary pump, which is on pin B10, and it didn't turn on. I hooked my volt meter to the output and set it to ohms, and when I triggered the output, it was reading 40-60 ohms. I'm wondering if I have the secondary pump wired incorrectly? Here is a pic of where it gets tied into the double pump harness: https://www.racetronix.com/product/F...PH-005-1-L.jpg I left one of those looped terminals in, so the factory relay turns on the pump. That part works fine, and is triggered by the green fuel pump output wire on the Holley.
If you look at the pic, there's a black ground wire on one side of the terminal, and a red (or blue) wire on the other side of the terminal. The black ground wire is grounded to a stud on the engine adjacent to the alternator. The red wire goes to a relay for pump 1, the blue goes to a relay for pump 2. I used the output on B10 ( Grey w/ black stripe ) and made a terminal so it plugs into the double pump harness and connects to the blue wire. The opposite cavity I left empty, as I assumed it was no longer needed. My sensor ground from my Terminator X is grounded to my unibody under my passenger side kick panel. I ground the paint to bare metal before screwing it in, so I know it's making a good ground. In the rear of the car where the dual pump harness relays are located, there's another ground which I also attached to the unibody. There is also this intermediate harness that plugs into my stock '98 wiring: https://cdn.racetronix.biz/mmrtx/ima...pg?w=800&h=800 It has a ground that bolts to a stud I installed on top of the sender. 3 wires come out of the harness and go into the factory bulkhead under the car. Grey is fuel pump command, purple and black are for the gas gauge ( which doesn't work, but that's another problem ). The output is functioning correctly from what I can see, but is the 40-60 ohm reading plausible? When I have the connector plugged in and command the output on, there's no reaction from the pump. I'm at a loss here, wiring is not my specialty.
Thread Starter
Joined: Apr 2006
Posts: 3,894
Likes: 1,139
From: Grand Rapids, Michigan
If you highlight the text within the post, even if you can't see it, it will show up. Highlight it the same as if you were copying and pasting the text. People do dark grey text on white all the time, and in dark mode, I can't read it. So I highlight the text and it then shows white on a blue background. Sorry about that!
Thread Starter
Joined: Apr 2006
Posts: 3,894
Likes: 1,139
From: Grand Rapids, Michigan
Yes, those triggers are defined, but when I do the output test, the pump doesn't turn on. Yet it turns on fine if I put the ground loop back in and let the factory relay trigger both of the the Racetronix relays. There's no way to control the pumps independently if I'm only using the green Holley output wire to trigger the factory relay to turn on both pumps. That's why I defined an output on B10 to turn on pump 2 over 3000 RPM and 2PSI boost. All the Racetronix relay is looking for is a ground switch. The output is providing it, but the pump still isn't turning on. I feel like I am missing something here, wiring-wise. I can't figure it out. The intermediate harness has 3 wires that plug into the factory bulkhead, one of which is the fuel pump trigger wire. The other two are for the fuel gauge. I feel like, the way the Racetronix intermediate harness is wired, unless the ground switch goes through the grey factory bulkhead trigger wire, the relay for the second pump will not energize. I may be wrong there, but I can't see any other reason why the relay won't turn on when the Holley output triggers it.
Yes, those triggers are defined, but when I do the output test, the pump doesn't turn on. Yet it turns on fine if I put the ground loop back in and let the factory relay trigger both of the the Racetronix relays. There's no way to control the pumps independently if I'm only using the green Holley output wire to trigger the factory relay to turn on both pumps. That's why I defined an output on B10 to turn on pump 2 over 3000 RPM and 2PSI boost. All the Racetronix relay is looking for is a ground switch. The output is providing it, but the pump still isn't turning on. I feel like I am missing something here, wiring-wise. I can't figure it out. The intermediate harness has 3 wires that plug into the factory bulkhead, one of which is the fuel pump trigger wire. The other two are for the fuel gauge. I feel like, the way the Racetronix intermediate harness is wired, unless the ground switch goes through the grey factory bulkhead trigger wire, the relay for the second pump will not energize. I may be wrong there, but I can't see any other reason why the relay won't turn on when the Holley output triggers it.
Thread Starter
Joined: Apr 2006
Posts: 3,894
Likes: 1,139
From: Grand Rapids, Michigan
I'll just add it in here since I did have another thread touching on it: The secondary fuel pump works as it should now. When I was doing output testing with the Terminator X, I hadn't thought about how the Racetronix relays get their power. It's coming from the factory bulkhead under the driver's rear of the car. So the only way to test it correctly is to disconnect the jumper from the main pump, then turn on the fuel pump output on the Terminator X, then turn on the secondary fuel pump output. When done this way, the pump turns on.
Launching!
Joined: Jul 2014
Posts: 295
Likes: 102
From: Duluth, Minnesota
I more or lessed ditched the Racetronix wiring and used the plugs but wired in relays for my fuel pumps to work with the Holley.
I will have to double check later but I am pretty sure with the Terminator we couldnt run the second pump off of a ground trigger as well and had to go with a 12v signal to activate the second pump.
Mine is set up to turn on at 3/4 throttle and works great.
If still need help I will look this afternoon.
I will have to double check later but I am pretty sure with the Terminator we couldnt run the second pump off of a ground trigger as well and had to go with a 12v signal to activate the second pump.
Mine is set up to turn on at 3/4 throttle and works great.
If still need help I will look this afternoon.
Thread Starter
Joined: Apr 2006
Posts: 3,894
Likes: 1,139
From: Grand Rapids, Michigan
Funny you posted that, as I think I have finally figured out my issue. The Terminator isn't the problem, the factory fuel pump circuit is. For some reason, it's cutting power to the relay when under load. I don't know if it's not receiving a crank/cam signal at higher RPM or what, but it's definitely what is causing all of my problems. I'm definitely able to trigger the second pump, everything works correctly - it just doesn't STAY working under load.