Mailorder tune , big problems after cam.
Thread Starter
Launching!
Joined: Jan 2010
Posts: 236
Likes: 0
From: Warrenton, VA
Mailorder tune , big problems after cam. So I got a 233/239 112lsa camshaft from texas speed, dual prc springs with new seats and titanium retainers, pacesetter headers, tsp true duals with dynomax bullets and a 3600 stall. All but the stall are in now. I got a mail order tune from Tunedbyfrost. I'll tell you what, I started it up and it idled perfectly, a little high, but it would hold an idle, but...10 minutes later missfires out the ***, sometimes i couldnt even idle without holding down the gas. I let it get nice and hot with my foot on the gas to 1500 rpms, (160 degrees) for it to go into "closed loop" no luck, let off and it idled for maybe 10 seconds before it died.
I'm gonna include a little video here i just uploaded, its missing bad, here u see it idles fine then has a VIOLENT missfire when i rev it up to 2000 rpms that literally makes the car shake. I think maybe the timing is to advanced? cars being towed to have the stall put in tomorrow. I'm going to tow it to richmond (2 hours away from me) and get it dynod by frost if it wont run. Never the less though, im very unhappy this car wont ******* hold idle.
http://www.youtube.com/watch?v=eG5fE...el_video_title
This is a 1998 camaro as well, just to let you guys know, with 51000 original miles.
I'm gonna include a little video here i just uploaded, its missing bad, here u see it idles fine then has a VIOLENT missfire when i rev it up to 2000 rpms that literally makes the car shake. I think maybe the timing is to advanced? cars being towed to have the stall put in tomorrow. I'm going to tow it to richmond (2 hours away from me) and get it dynod by frost if it wont run. Never the less though, im very unhappy this car wont ******* hold idle.
http://www.youtube.com/watch?v=eG5fE...el_video_title
This is a 1998 camaro as well, just to let you guys know, with 51000 original miles.
Last edited by ripfirebird94; May 10, 2011 at 07:18 PM. Reason: i meant towed, not tuned
Thread Starter
Launching!
Joined: Jan 2010
Posts: 236
Likes: 0
From: Warrenton, VA
Maybe, I havnt been able to drive it due to not having the stall, it pops really ******* bad, maybe I can deal with it and drive it a little after the stall, see if it mellows out? New plugs, but wires are stock. Again only 50,000 miles, nothing major mechanically is wrong. I know camshaft is degreed well because i can crank it without the coil packs plugged in and its not smacking the pistons or anything, it cranks up with no noise, but plug the packs in and its missing like a bitch, anyway I could have wired the coil packs wrong? I was having some problems and its really messy.
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It will put the car to the speed density table and if it runs perfect the maf is bad. You have understand a tune is not organic, it doesnt go bad after ten minutes of run time. Check the connections back at the ecm too. Again, the issue is mechanical, not tune related
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Staging Lane
Joined: May 2008
Posts: 89
Likes: 0
From: Washington State
I had close to the same problem, but on the dyno while tuning. The **** burning out of the inside of the headers (coated pacesetters) killed both of my O2's. They would flat line at idle and off idle would jump from 0.2 volts to 0.9. Swap O2's or data log to see exactly what is going on. May not be your problem but something to check.
double check how the coils are wired before doing the 02's. Your problem is definitely ignition related. I would go as far as checking the plugs too had it not run well for 10 minutes first. The stock plug wires have a habit of coming apart inside the boots too.
DOUBLECHECK everything before you throw parts at it....
DOUBLECHECK everything before you throw parts at it....
On The Tree
Joined: Mar 2009
Posts: 175
Likes: 1
From: shrewsbury, ma
an o2 sensor will not make it do what you are saying. i would try the maf just because its easy. check the basics..did one of the plugs get pinched closed when you were installing them..doesnt take much. are there any air leaks you can hear around the intake? i know its hard with the exhaust.
"I know camshaft is degreed well because i can crank it without the coil packs plugged in and its not smacking the pistons or anything" this scares me.
what do you mean you may have wired the coil packs uncorrectly? is there any way you can find which cylinder is missing..any access to a scanner of some sort. this would get you in the right direction the quickest.
"I know camshaft is degreed well because i can crank it without the coil packs plugged in and its not smacking the pistons or anything" this scares me.
what do you mean you may have wired the coil packs uncorrectly? is there any way you can find which cylinder is missing..any access to a scanner of some sort. this would get you in the right direction the quickest.
11 Second Club
Joined: Oct 2006
Posts: 149
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Disconnect the power to the pcm so all it's learned data is erased. Then restart it & see how it goes. If it starts fine, you are learning bad data which needs to be addressed.
If it still misses, something mechanical is causing the issue. Disconnect the injectors one at a time while running to isolate which cylinder is bad.
If it still misses, something mechanical is causing the issue. Disconnect the injectors one at a time while running to isolate which cylinder is bad.
The misfire is something real and physical to find. Your timing isn't too advanced; it's lower than stock at no-load up to around 21-2300 RPMs except for deep decel.
The fact that it's ok during first startup (no correction from O2's; open loop) and then, once it goes into closed loop it runs poorly just re-enforces a plain old misfiring cylinder. The misfiring cylinder passes off it's unused oxygen content to the front O2 on the side with the issue. The PCM is a little dumb and mistakes this misfiring cylinder for a lean condition and begins adding away at the fuel to try to 'fix' what it thinks is a lean condition. It can't, and it over fuels that side of the engine as a result. As this adding goes on, the car will run worse and worse.
To figure out which side of the engine the misfire is occurring on (if you have a scanner), look for the side that has very high positive long and short term trims. That's the problem side.
Alternately, unhook the O2s and the car will run open loop. Unhook the battery and it will reset previous learning. You can then run the car in open loop to search for the problem more safely because the PCM won't drown the offending side with closed loop operation.
There is a real physical problem here. We can certainly get it fixed for you if you'd like, and I'd be happy to answer any questions.
Thread Starter
Launching!
Joined: Jan 2010
Posts: 236
Likes: 0
From: Warrenton, VA
In regards to the intial high idle... The PCM shipped with a sheet that explains how to setup the throttle body's blade screw. It tells you how to do it with a scanner (via IAC steps) and how to feel it out based on idle and small adjustments with no scanner.
The misfire is something real and physical to find. Your timing isn't too advanced; it's lower than stock at no-load up to around 21-2300 RPMs except for deep decel.
The fact that it's ok during first startup (no correction from O2's; open loop) and then, once it goes into closed loop it runs poorly just re-enforces a plain old misfiring cylinder. The misfiring cylinder passes off it's unused oxygen content to the front O2 on the side with the issue. The PCM is a little dumb and mistakes this misfiring cylinder for a lean condition and begins adding away at the fuel to try to 'fix' what it thinks is a lean condition. It can't, and it over fuels that side of the engine as a result. As this adding goes on, the car will run worse and worse.
To figure out which side of the engine the misfire is occurring on (if you have a scanner), look for the side that has very high positive long and short term trims. That's the problem side.
Alternately, unhook the O2s and the car will run open loop. Unhook the battery and it will reset previous learning. You can then run the car in open loop to search for the problem more safely because the PCM won't drown the offending side with closed loop operation.
There is a real physical problem here. We can certainly get it fixed for you if you'd like, and I'd be happy to answer any questions.
The misfire is something real and physical to find. Your timing isn't too advanced; it's lower than stock at no-load up to around 21-2300 RPMs except for deep decel.
The fact that it's ok during first startup (no correction from O2's; open loop) and then, once it goes into closed loop it runs poorly just re-enforces a plain old misfiring cylinder. The misfiring cylinder passes off it's unused oxygen content to the front O2 on the side with the issue. The PCM is a little dumb and mistakes this misfiring cylinder for a lean condition and begins adding away at the fuel to try to 'fix' what it thinks is a lean condition. It can't, and it over fuels that side of the engine as a result. As this adding goes on, the car will run worse and worse.
To figure out which side of the engine the misfire is occurring on (if you have a scanner), look for the side that has very high positive long and short term trims. That's the problem side.
Alternately, unhook the O2s and the car will run open loop. Unhook the battery and it will reset previous learning. You can then run the car in open loop to search for the problem more safely because the PCM won't drown the offending side with closed loop operation.
There is a real physical problem here. We can certainly get it fixed for you if you'd like, and I'd be happy to answer any questions.