What is wrong????
Thread Starter
Instructor
Joined: Jan 2005
Posts: 204
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What is wrong????
My car does not seem to be liking the gas pedal.......I have sputtering at idle intermittent sputtering at speed and overall sluggishness. I used the paperclip and got code 15, 33, and 42. Not sure what these mean but i know that the 15 is because my coolant temp sensor wire is burnt through just havent put in the new wiring harness.
Fuel pressure drop from 40psi at idle to 0 in like 2 minutes. I did the pinch of the return line and i determined that it isnt anytyhing in the pump. Ohmed the injectors and all seem to be around 17 ohms. I am getting a nasty ticking around the passanger bank. It almost sound like a bad exhuast leak but i cant tell. Does this sound like maybe a stuck lifter or bent pushrod??? someone please help me on this.
Fuel pressure drop from 40psi at idle to 0 in like 2 minutes. I did the pinch of the return line and i determined that it isnt anytyhing in the pump. Ohmed the injectors and all seem to be around 17 ohms. I am getting a nasty ticking around the passanger bank. It almost sound like a bad exhuast leak but i cant tell. Does this sound like maybe a stuck lifter or bent pushrod??? someone please help me on this.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
That is a fast leak down. Look in your FPR vac and see if there is gas there. If not I suspect injecotors but if all are around 17 that is good. I would not do anything until I fixed the codes. The code 15 will hurt the most. Repair the wire disconnect the battery for 30 sec, and see whats left.
Team Owner
Joined: Jan 2003
Posts: 20,304
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From: Summerland B.C. Canada
http://members.shaw.ca/corvette86/Code%2015.pdf
http://members.shaw.ca/corvette86/Code%2033.pdf
http://members.shaw.ca/corvette86/Code%2042.pdf
A bad CTS can really mess up driveability if you ECM thinks you coolant is ice.
http://members.shaw.ca/corvette86/Code%2033.pdf
http://members.shaw.ca/corvette86/Code%2042.pdf
A bad CTS can really mess up driveability if you ECM thinks you coolant is ice.
Race Director
Joined: Feb 2004
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Originally Posted by AGENT 86
http://members.shaw.ca/corvette86/Code%2015.pdf
http://members.shaw.ca/corvette86/Code%2033.pdf
http://members.shaw.ca/corvette86/Code%2042.pdf
A bad CTS can really mess up driveability if you ECM thinks you coolant is ice.
http://members.shaw.ca/corvette86/Code%2033.pdf
http://members.shaw.ca/corvette86/Code%2042.pdf
A bad CTS can really mess up driveability if you ECM thinks you coolant is ice.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
on that CTS..fix that first, did you ohm the injectors warm and cold? that fuel pressure is going somewhere-only 3 areas it can go, injectors (leaking) fuel pressure regulator-or back into the tank either through a bad check valve in the FP or, one guy found a fuel pump pulsator was his culprit.Add a fourth, leak in the fuel line.Like Pete said, work out the solutions to the codes first.
Thread Starter
Instructor
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I have a wiring harness laying around i have yet to install. The harness is a hack job of someone trying to to something but never really did anything but give me a SES light...lol. I am going to try installing that and see if drivability improves. I tried clamping the return line going to the fuel pump after i had pressure in the line. the pressure stayed for a second and then drained down over a period of like 5 minutes. injectors were ohmed hot so i am not sure if that has anything to do with it. Also upon heavy acceleration i get a little cloud of blue smoke out of the tailpipes.....could be the seafoam i put in there.....
on the code 33....a few months ago i thought i replaced the maf relays and i did replace the maf...the two relays are the ones right above the battery right?? My friend and i were looking at them last night and he swears they are for the fans and fuel pump...anyone??
on the code 33....a few months ago i thought i replaced the maf relays and i did replace the maf...the two relays are the ones right above the battery right?? My friend and i were looking at them last night and he swears they are for the fans and fuel pump...anyone??
Last edited by Mtrhd329; May 21, 2006 at 01:11 PM.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Originally Posted by Mtrhd329
I have a wiring harness laying around i have yet to install. The harness is a hack job of someone trying to to something but never really did anything but give me a SES light...lol. I am going to try installing that and see if drivability improves. I tried clamping the return line going to the fuel pump after i had pressure in the line. the pressure stayed for a second and then drained down over a period of like 5 minutes. injectors were ohmed hot so i am not sure if that has anything to do with it. Also upon heavy acceleration i get a little cloud of blue smoke out of the tailpipes.....could be the seafoam i put in there.....
on the code 33....a few months ago i thought i replaced the maf relays and i did replace the maf...the two relays are the ones right above the battery right?? My friend and i were looking at them last night and he swears they are for the fans and fuel pump...anyone??
on the code 33....a few months ago i thought i replaced the maf relays and i did replace the maf...the two relays are the ones right above the battery right?? My friend and i were looking at them last night and he swears they are for the fans and fuel pump...anyone??
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Thread Starter
Instructor
Joined: Jan 2005
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ok good to hear about the relays i replaced the right ones.
I was thinking it had to be something in the fuel rail but could the injectors be bad if they all ohmed out to about 17 ohms?? if not i will replace the regualtor. could that be the ticking noise??
I was thinking it had to be something in the fuel rail but could the injectors be bad if they all ohmed out to about 17 ohms?? if not i will replace the regualtor. could that be the ticking noise??
Le Mans Master
Joined: Jan 2006
Posts: 6,564
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From: Woodstock Georgia
Originally Posted by Mtrhd329
ok good to hear about the relays i replaced the right ones. I was thinking it had to be something in the fuel rail but could the injectors be bad if they all ohmed out to about 17 ohms?? if not i will replace the regualtor. could that be the ticking noise??
I was thinking it had to be something in the fuel rail but could the injectors be bad if they all ohmed out to about 17 ohms?? if not i will replace the regualtor. could that be the ticking noise??
Le Mans Master
Joined: Dec 2000
Posts: 7,839
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From: San Diego, Ca
The codes probably have it running on backup and you do need to diagnose the injectors. Otherwise, your CTS is comparable to a choke and an open circuit means the ECM is sensing -32 degrees. So if it isn't running on backup, it's dumping max fuel through the injectors from startup to running temp and they don't run very well when they're flooded.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
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From: seattle WA
SunCr, help me with a little clarification if you will? I've heard perfectly good injectors clicking before....no pressure loss, no missing! Yet, I've heard folks say if they're clicking they're bad!! IMHO, if you have good hearing, you should be able to hear them click...what do you think???
Thread Starter
Instructor
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ok thanks!!! i will put the new harness on tonight and then check on injector prices....so is there any test i can do to determine if it is in fact the injectors or the regulator before i buy anything? I have no gas in the vaccuum line to the regualtor and it seems to regulate pressure ok(besides the variations...only a few psi each way but consistent with idle)
Also the new wiring harness and the existing CTS have different connectors. Does anyone know the P/N for this peice? The one in it says TSU81 from the best i can read it. Thanks again guys!!
Also the new wiring harness and the existing CTS have different connectors. Does anyone know the P/N for this peice? The one in it says TSU81 from the best i can read it. Thanks again guys!!
Last edited by Mtrhd329; May 22, 2006 at 08:01 AM.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
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From: San Diego, Ca
Mtrhd329: GM has used the same CTS across all lines forever. Signal is always Yellow, Ground Black and spliced to the Manifold Air Temp Sensor and the TPS. Sure it's GM harness? Otherwise, a replacement CTS will you set you back $9 and it will include a new pigtail.
Rick: Injector noise is normal. A basic diagnostic test is to make sure they're clicking. The aftermarket ones (I'm using a cheapo set of Accels), seem to "click" louder than the OEMS - at least mine do.
Bill
Rick: Injector noise is normal. A basic diagnostic test is to make sure they're clicking. The aftermarket ones (I'm using a cheapo set of Accels), seem to "click" louder than the OEMS - at least mine do.
Bill
Racer
Joined: May 2006
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From: Alpine California
Yes, you should here them quietly clicking (some not so quiet, especially aftermarket or OEM with a lot of miles. Now this is an extreme case, but I recently looked at a stock 1986 that you could here the inj. from 10 feet away with the hood closed. Car still ran good, but that's too loud. You know their on their last legs! Correct me if I'm wrong, but Ohm'ing the injectors only tells you if the coil is good, they could still have a mechanical seal (pintle) leaking and Ohm good, right?
Le Mans Master
Joined: Oct 2003
Posts: 6,130
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From: seattle WA
Blownfuel, you're right as far as Ohming them, that only lets you know if the coils are good..bad coils..bad injectors, you need to do a fuel pressure test also, the coils can be good..but the injectors can still be clogged or leaking...but as far as clicking..a few of us would disagree with that. 
Plus you should also use a noid light to see if the signal is actually getting to the injector(s).
Plus you should also use a noid light to see if the signal is actually getting to the injector(s).
Le Mans Master
Joined: Jan 2006
Posts: 6,564
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From: Woodstock Georgia
Originally Posted by rick lambert
Blownfuel, you're right as far as Ohming them, that only lets you know if the coils are good..bad coils..bad injectors, you need to do a fuel pressure test also, the coils can be good..but the injectors can still be clogged or leaking...but as far as clicking..a few of us would disagree with that. Plus you should also use a noid light to see if the signal is actually getting to the injector(s).
Plus you should also use a noid light to see if the signal is actually getting to the injector(s).Am I making sense, or missing something?
Thread Starter
Instructor
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I will check the plugs and see what they look like i didnt think of that. i guess its time for injectors and a regulator anyway...thanks for the help guys you always come through
UPDATE- so i found the source of the code 15 problem....there was a IAT extension done and i guess he got some wires mixed up because the ground for the CTS was used for the ground. I reran new wires from the ECM for both and it seems to be doing fine now. Idles a lot better i am going to try and get code 33 to go away now and see how it runs after some more beers
UPDATE- so i found the source of the code 15 problem....there was a IAT extension done and i guess he got some wires mixed up because the ground for the CTS was used for the ground. I reran new wires from the ECM for both and it seems to be doing fine now. Idles a lot better i am going to try and get code 33 to go away now and see how it runs after some more beers
Last edited by Mtrhd329; May 23, 2006 at 11:54 AM.