found the problem but its very weird!! -- need some help
found the problem but its very weird!! -- need some help In case you haven't been following -- basically I had a problem with my TT install. The passenger side manifold would beging to glow after only idling for 5 minutes.
So today I took the whole passenger side off and checked everything for leaks, cracks, whatever. Everything looked fine, put it back together. Loosened, then re-torqued the rockers on that side. Spun the motor over with the valve cover off and everything looks good. So put a fresh round of oil in it and started it up. Fuel pressure still rock solid, and sure enough after about 5 minutes of idling it heats up to red hot.
(also, previously the injectors have been swapped side to side).
Ok so then a friend came over and we started messing with things trying to figure it out. Here's what we found.
If you pull one plug off the injector (leaving only 3 firing on that side), the maifold will NOT heat up to red hot, but shortly after plugging the 4th injector in the manifold will get red hot. It doesn't matter which injector you disable, as long as one is disconnected the manifold won't heat up.
So it has to be dumping way to much fuel and that 4th injector is enough to push it to the redhot stage. Mind you that running on 3 injectors on that side it wasn't dead cool either so its still dumping way to much fuel.
But here is the problem, how in the hell do I fix that if its in the wiring and only that side???
BTW, checked all the fuses and they are all set as well.
So today I took the whole passenger side off and checked everything for leaks, cracks, whatever. Everything looked fine, put it back together. Loosened, then re-torqued the rockers on that side. Spun the motor over with the valve cover off and everything looks good. So put a fresh round of oil in it and started it up. Fuel pressure still rock solid, and sure enough after about 5 minutes of idling it heats up to red hot.
(also, previously the injectors have been swapped side to side).
Ok so then a friend came over and we started messing with things trying to figure it out. Here's what we found.
If you pull one plug off the injector (leaving only 3 firing on that side), the maifold will NOT heat up to red hot, but shortly after plugging the 4th injector in the manifold will get red hot. It doesn't matter which injector you disable, as long as one is disconnected the manifold won't heat up.
So it has to be dumping way to much fuel and that 4th injector is enough to push it to the redhot stage. Mind you that running on 3 injectors on that side it wasn't dead cool either so its still dumping way to much fuel.
But here is the problem, how in the hell do I fix that if its in the wiring and only that side???
BTW, checked all the fuses and they are all set as well.
Last edited by Classic; Aug 1, 2004 at 12:40 AM.
have you tried any diagnostics that would show injector activity? like ATAP? the swapping of injectors rules them out but not the PCM and interconnections which command them.
did you swap the front O2 sensors? they provide one piece of data that is used to calculate fuel injection amount in closed loop.
Are you sure there is no downstream blockage in the exhaust sys? does the turbo spin?
did you swap the front O2 sensors? they provide one piece of data that is used to calculate fuel injection amount in closed loop.
Are you sure there is no downstream blockage in the exhaust sys? does the turbo spin?
Yep, swapped 02 sensors, still same problem. Injector duty cycle is the same for both sides acording to EFIlive.
There really can't be any downstream blockage because right now its just running straight out the down pipe (about 18-20 inches downstream of the turbo). The rest of the exhaust isn't even on yet since I have to have a custom ypipe made up.
Turbo spins freely. The only thing I could think is possibly the waste gate??? I guess the next thing I'll try is swapping the waste gates side to side.
There really can't be any downstream blockage because right now its just running straight out the down pipe (about 18-20 inches downstream of the turbo). The rest of the exhaust isn't even on yet since I have to have a custom ypipe made up.
Turbo spins freely. The only thing I could think is possibly the waste gate??? I guess the next thing I'll try is swapping the waste gates side to side.
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From: Jersey boy
usually running rich will make you run cooler and running lean makes you hotter. also if youre running that rich you would probably smell it and know that somethings up.
did you have it tuned? does it still glow,or start glowing sooner if you give it some gas/rpm?
it really sounds to me like you have some kind of restriction in the pipe, have you tried snaking something through there and making sure its not clogged?
did you have it tuned? does it still glow,or start glowing sooner if you give it some gas/rpm?
it really sounds to me like you have some kind of restriction in the pipe, have you tried snaking something through there and making sure its not clogged?
There are no restrictions -- checked everything yesterday. I took the manifold off checked it out, looks fine nothing sticking in any of the primaries. checked out the turbo, spins freely, nothing stuck in the waste gate port. Nothing stuck in the down pipe (I mean its only 20 inches long or so and its a straight shot out under the car (no ypipe, cat, muffler, anything at the moment).
Giving it gas doesn't affect anything (although it hasn't been above 2000-2500 rpms at the very most). If you unplug one of the injectors you can even give it gas and it won't heat up to red hot -- doesn't matter which injector I dissable either.
It has a "base" tune in it (basically Noyzee's old tune with some changes to make it "safe" until I get it on the dyno. Mind you this is essentially initial startup after all this stuff was put on. The car has not seen any boost, car hasn't even been driven yet. I checked the program today to see if I saw anything out of the ordinary and didn't find anything. So I'm kind of stuck.
Giving it gas doesn't affect anything (although it hasn't been above 2000-2500 rpms at the very most). If you unplug one of the injectors you can even give it gas and it won't heat up to red hot -- doesn't matter which injector I dissable either.
It has a "base" tune in it (basically Noyzee's old tune with some changes to make it "safe" until I get it on the dyno. Mind you this is essentially initial startup after all this stuff was put on. The car has not seen any boost, car hasn't even been driven yet. I checked the program today to see if I saw anything out of the ordinary and didn't find anything. So I'm kind of stuck.
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Read the O2's to determine if its truly rich or lean. If it stays up around 800mv+ its rich, 300mv- its lean. If it cycles rich to lean its probably something else. You should ohm test the injectors also.
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From: Jersey boy
i dont think it has anything to do with the tune because only the passenger side is affected. have you tryed idling without the turbo on that side? ie, removing it and starting the car? or removing both and starting the car? are the 2 manifolds symetrical? equal length, same amount of bends in each?
Ok, just got back inside from working on it -- I pulled the down pipe to check for obstructions, again checked the turbo (spins freely), no restrictions in the down pipe. Put it back together, checked plug wires again, started it up, and sure enough its running RICH. At start up both 02s start out at 430 mv, then after a minute and a half or two, the passenger 02 starts to steadily climb to about 900mv where it holds.
BigPlan -- haven't tried idling without the turbo on that side. Both manifolds are symetrical, almost identical actually. No extra bends or anything.
How can ONE SIDE get to much fuel since its still running a stock computer (with programming but no FAST, DFI, etc.)? The 02 looks like its working just fine, plus I swapped it with 3 others and got the same values being rich.
Also, remember I swapped injectors side to side so if the injectors were the problem the problem would have moved to the drivers side but it didn't.
BigPlan -- haven't tried idling without the turbo on that side. Both manifolds are symetrical, almost identical actually. No extra bends or anything.
How can ONE SIDE get to much fuel since its still running a stock computer (with programming but no FAST, DFI, etc.)? The 02 looks like its working just fine, plus I swapped it with 3 others and got the same values being rich.
Also, remember I swapped injectors side to side so if the injectors were the problem the problem would have moved to the drivers side but it didn't.
Also, remember this isn't something that just happened after I had been driving the car around for months. This is still basically the first time the car has been run since the install of the TT setup. Also, didn't have any problems previous to this as my H/C setups ran very nicely.
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Originally Posted by Classic
Also, remember this isn't something that just happened after I had been driving the car around for months. This is still basically the first time the car has been run since the install of the TT setup. Also, didn't have any problems previous to this as my H/C setups ran very nicely.
1) Can you show us a pic of your setup.
2) (more of a question) is your COTS enabled, and does COTS dump fuel in both sides if one side is overtemp, or both sides?
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From: Las Cruces, NM
Originally Posted by Classic
In case you haven't been following -- basically I had a problem with my TT install. The passenger side manifold would beging to glow after only idling for 5 minutes.
So today I took the whole passenger side off and checked everything for leaks, cracks, whatever. Everything looked fine, put it back together. Loosened, then re-torqued the rockers on that side. Spun the motor over with the valve cover off and everything looks good. So put a fresh round of oil in it and started it up. Fuel pressure still rock solid, and sure enough after about 5 minutes of idling it heats up to red hot.
(also, previously the injectors have been swapped side to side).
Ok so then a friend came over and we started messing with things trying to figure it out. Here's what we found.
If you pull one plug off the injector (leaving only 3 firing on that side), the maifold will NOT heat up to red hot, but shortly after plugging the 4th injector in the manifold will get red hot. It doesn't matter which injector you disable, as long as one is disconnected the manifold won't heat up.
So it has to be dumping way to much fuel and that 4th injector is enough to push it to the redhot stage. Mind you that running on 3 injectors on that side it wasn't dead cool either so its still dumping way to much fuel.
But here is the problem, how in the hell do I fix that if its in the wiring and only that side???
BTW, checked all the fuses and they are all set as well.
So today I took the whole passenger side off and checked everything for leaks, cracks, whatever. Everything looked fine, put it back together. Loosened, then re-torqued the rockers on that side. Spun the motor over with the valve cover off and everything looks good. So put a fresh round of oil in it and started it up. Fuel pressure still rock solid, and sure enough after about 5 minutes of idling it heats up to red hot.
(also, previously the injectors have been swapped side to side).
Ok so then a friend came over and we started messing with things trying to figure it out. Here's what we found.
If you pull one plug off the injector (leaving only 3 firing on that side), the maifold will NOT heat up to red hot, but shortly after plugging the 4th injector in the manifold will get red hot. It doesn't matter which injector you disable, as long as one is disconnected the manifold won't heat up.
So it has to be dumping way to much fuel and that 4th injector is enough to push it to the redhot stage. Mind you that running on 3 injectors on that side it wasn't dead cool either so its still dumping way to much fuel.
But here is the problem, how in the hell do I fix that if its in the wiring and only that side???
BTW, checked all the fuses and they are all set as well.
Are these stock injectors if not I assume you have tuning for the injectors -ifr and injector offset? Checked each injector for proper operation and no leaks? Misfire of course will cause exactly what you are seeing and so will puddling or a lean condition. If you can't find anything wrong with everything external to the engine then you know where to look after that.
Gary
"At start up both 02s start out at 430 mv, then after a minute and a half or two, the passenger 02 starts to steadily climb to about 900mv where it holds."
you probably know this, but on a cold start the engine runs in open loop mode until the O2 sensors can provide reading, then it goes into closed loop. I have an onboard wideband and the car runs rich until it hits closed loop then goes to 14.7.
this is a stumper
If I were'nt traveling, I'd crack open the Helms books to see if there is any insight in the factory manuals. I assume you've cheked for DTC's and there are none.
you probably know this, but on a cold start the engine runs in open loop mode until the O2 sensors can provide reading, then it goes into closed loop. I have an onboard wideband and the car runs rich until it hits closed loop then goes to 14.7.
this is a stumper
If I were'nt traveling, I'd crack open the Helms books to see if there is any insight in the factory manuals. I assume you've cheked for DTC's and there are none. 
Good thought on open loop -- I'll give that a try tomorrow morning.
Injectors are not stock -- they are 50lb injectors. They have been compensated for in the computer.
The wiring harness is good to go plugged in correctly.
Allready eliminated the injectors they have been swapped side to side and the problem didn't swap sides with them.
Injectors are not stock -- they are 50lb injectors. They have been compensated for in the computer.
The wiring harness is good to go plugged in correctly.
Allready eliminated the injectors they have been swapped side to side and the problem didn't swap sides with them.
Hmm, I just had a thought -- since the exhaust basically ends at the downpipe (shortly after the 02 sensor) could ambient air be getting to the 02 sensor causing it to dump fuel? Similar to running just open headers without turndown kind of scenario maybe.
no they aren't exactly the same at the moment. See Brad (Noyzee) had cutouts in both downpipes but they wouldn't work with my subframe connectors so I had to cut them off so they aren't "exactly" the same anymore. That COULD be it, but I don't know. It will have to wait till tomorrow so the neighboors don't have me kicked out 
The injector tables were pulled straight from Brad's old program and also, if they weren't set up right both sides would have the problem correct??
The injector tables were pulled straight from Brad's old program and also, if they weren't set up right both sides would have the problem correct??
Last edited by Classic; Aug 1, 2004 at 10:02 PM.
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From: Las Cruces, NM
Originally Posted by Classic
no they aren't exactly the same at the moment. See Brad (Noyzee) had cutouts in both downpipes but they wouldn't work with my subframe connectors so I had to cut them off so they aren't "exactly" the same anymore. That COULD be it, but I don't know. It will have to wait till tomorrow so the neighboors don't have me kicked out
The injector tables were pulled straight from Brad's old program and also, if they weren't set up right both sides would have the problem correct??
The injector tables were pulled straight from Brad's old program and also, if they weren't set up right both sides would have the problem correct??
I assume on the 50 lb injectors that you did change the injector offset table since the injectors are about twice as slow as stock in opening (not just fudged the injector flowrate table). Although I do not think this is the problem.
Gary