Recently I replaced the head gaskets on my 99' GMC Suburban. Since then I have had the SES light on. When I run the codes it comes up misfire. I have replaced everything from the ICM to the plugs. There's a black plug in the middle of the intake with a white safety clip on it and I'm wondering if that isn't the problem. When I replaced the ICM, the coil, and plug wires it wouldn't start. I noticed that the white clip had come lose and reconnected it...and it started. Any ideas??? I just want the #$% light off. :shock:
Service Engine Soon Light
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Are the knock sensor, and misfire codes the same?
Did you re-time the engine, or just mark the distributor, and then replace it at the mark?
Or is this a DIS system?
Did you re-time the engine, or just mark the distributor, and then replace it at the mark?
Or is this a DIS system?
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it would throw the timing off, and I'm not sure what degree off it would be at one tooth, but yes, it could cause backfiring, but you'd also have poor performance too.
It runs fine, no miss at all. The only difference there is between before/after is the SES light. I was going to try moving the distributor a tooth today, but mother nature had other plans and we're under a blizzard warning. When the weather breaks I'll give it a shot and let you know how it comes out. 
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1,625 Posts
Pull the bulb
Sorry but thats just the easy way.
Sorry but thats just the easy way.
I had a similar problem after replacing my intake manifold gasket. No problem before the job, but when i was done I came up with codes indicating the catalytic converter is bad or something like that. I ran it for a little while, then had to disconnect battery for an unrelated issue. After reconnecting the battery, the light didn't come on again. I then went for the emissions test and everything was fine...so I still don't know what the problem really was...
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Wrong code?
I checked the manual that came with my code reader and P1349 decodes as: P1349 Intake Camshaft Position System. This sounds like an erroneous code since this code would be for dual overhead cam engines. Any new info on the code?cornboy said:That sounds very close to the code I'm getting (P 1349) camsaft-crankshaft correlation. I tried advancing the distributor a tooth and it wouldn't hardly start. I'll try retarding a tooth and see what happens. Thanks for the input!
Have any of you experienced a bad cam position sensor? From what I have read about it the truck will still run but the fuel injection goes off memory for each cylinder. I have to get my meter out before it snows again and check it. Any words of wisdom??
I went to Advance Auto tonight (finally) and ran it for codes again. It comes up P1345 which according to the haynes manual is a camshaft/crankshaft correlation problem. The OBD-II scanner comes reads misfire. I am almost tempted to replace the PCM, which they have for $108. I still want to check the camshaft position sensor with my meter, but not while its -5 degrees. My fingers don't work too well with it that cold. What do you all think??? :?:
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2,428 Posts
P1345 Code Solved!
OK, after extensive googling I found this post at another forum which should help. Read the entire thread at: automotiveforums.com
gregory914
10-31-2004, 02:40 PM
Click Here!
Does anyone know any details on the P1345 code? About three months ago I resset my OBDII, it only had one code (the one above) and the device said "engine misfire". Wich I assumed was from one of the times I shut the truck off to get the damn wipers to park in the down position, by shutting it off then quickly restarting it. For the last week or so it's been coming on almost every day at least once and stays on for a while then goes off and may not come on till the next day or two or three.
I stopped at my local Auto-Zone store and they got the same code that was stored before, P1345 and "ignition engine misfire" text. They ran it through their computer inside the store and it said "SGC (Cam Position) Sensor Circuit Malfunction". Does this mean the cam sensor is bad? And when do I really need to replace it? The truck runs fine and fast, has 109k miles on it and the milage is 12-13 mpg in the city stop and go, and I consistantly get 17.7 on the freeway doing about 80-85 mph. I also just put a new fuel pump and filter in about 900 miles ago and gained about 30-40 HP!(or so it seemed). The only mod to the truck is a K&N air filter in the factory optional "High Capacity Air Cleaner".
If it is a Cam Sensor, how do you know when it's not working and how do you change it? I was also wondering if it could be the electrical connection to or from the sensor. I bought my Burb new, it is a 97 K1500 with 109k miles and has had doses of Techron twice a year and only eats premium fuel. I have never had any codes except for an O2 sensor thet was replaced under warranty at 40k miles.
Any HELP!!!
THANKS
gregory914
06-29-2005, 09:56 AM
I have finaly figured out what my problem code was telling me. Jeremy-WI and I were both on the right track, the code was correct in reporting the crank and distributor were out of sync. I thought the weak link would have been the cam chain but as it turns out it IS the distibutor gear.
Last week I went to my buddies shop to balance my tires and I metioned about having the SES light on for about a year now and that the code was for a cam position/ crank timing. He then proceeded to tell me that in the 97 and 98s, as his K2500 P'up is, that the gears were soft and they would actualy wear enough to through off the timing and you could try to adjust the timing but at some point you'll run out of adjustment.
The real big problem, that happened to him was that gear is also hooked to the oil pump and he lent his truck to his son's Boy Scout troop and wile going down the freeway at 75 or so it strated to mis-fire and backfire because the timing was so far off and yes the oil pressure went to ZERO and Paul now has a new GM factory replacement long block in his truck($2750) and he did the swap out himself.
Until six months ago he didn't realized this is a common problem with that vintage of GM distributors because you could usually adjust the timing enough to get the code to go away but you are just masking the real problem. He is a GM certified Tech, worked at an Olds dealer for 10 years before opening his own place, but he had never herd of this as being common. He then proceeded to show me a box with about 25 to 30 gears all worn the same way and all from 96 thruogh 99s that had SES lights on. And now with a $40 part and less than two hours labor and ten minutes on a scanner all these 100K mile trucks run fine and can pass our E-check here in Ohio.
So before you start buying sensors and other misc. parts , try the gear if you are getting a P1345 code. I was surprised at the wear because I religously used Mobil 1 and can only put the cause on the GM parts supplier.
OK, after extensive googling I found this post at another forum which should help. Read the entire thread at: automotiveforums.com
gregory914
10-31-2004, 02:40 PM
Click Here!
Does anyone know any details on the P1345 code? About three months ago I resset my OBDII, it only had one code (the one above) and the device said "engine misfire". Wich I assumed was from one of the times I shut the truck off to get the damn wipers to park in the down position, by shutting it off then quickly restarting it. For the last week or so it's been coming on almost every day at least once and stays on for a while then goes off and may not come on till the next day or two or three.
I stopped at my local Auto-Zone store and they got the same code that was stored before, P1345 and "ignition engine misfire" text. They ran it through their computer inside the store and it said "SGC (Cam Position) Sensor Circuit Malfunction". Does this mean the cam sensor is bad? And when do I really need to replace it? The truck runs fine and fast, has 109k miles on it and the milage is 12-13 mpg in the city stop and go, and I consistantly get 17.7 on the freeway doing about 80-85 mph. I also just put a new fuel pump and filter in about 900 miles ago and gained about 30-40 HP!(or so it seemed). The only mod to the truck is a K&N air filter in the factory optional "High Capacity Air Cleaner".
If it is a Cam Sensor, how do you know when it's not working and how do you change it? I was also wondering if it could be the electrical connection to or from the sensor. I bought my Burb new, it is a 97 K1500 with 109k miles and has had doses of Techron twice a year and only eats premium fuel. I have never had any codes except for an O2 sensor thet was replaced under warranty at 40k miles.
Any HELP!!!
THANKS
gregory914
06-29-2005, 09:56 AM
I have finaly figured out what my problem code was telling me. Jeremy-WI and I were both on the right track, the code was correct in reporting the crank and distributor were out of sync. I thought the weak link would have been the cam chain but as it turns out it IS the distibutor gear.
Last week I went to my buddies shop to balance my tires and I metioned about having the SES light on for about a year now and that the code was for a cam position/ crank timing. He then proceeded to tell me that in the 97 and 98s, as his K2500 P'up is, that the gears were soft and they would actualy wear enough to through off the timing and you could try to adjust the timing but at some point you'll run out of adjustment.
The real big problem, that happened to him was that gear is also hooked to the oil pump and he lent his truck to his son's Boy Scout troop and wile going down the freeway at 75 or so it strated to mis-fire and backfire because the timing was so far off and yes the oil pressure went to ZERO
and Paul now has a new GM factory replacement long block in his truck($2750) and he did the swap out himself.Until six months ago he didn't realized this is a common problem with that vintage of GM distributors because you could usually adjust the timing enough to get the code to go away but you are just masking the real problem. He is a GM certified Tech, worked at an Olds dealer for 10 years before opening his own place, but he had never herd of this as being common. He then proceeded to show me a box with about 25 to 30 gears all worn the same way and all from 96 thruogh 99s that had SES lights on. And now with a $40 part and less than two hours labor and ten minutes on a scanner all these 100K mile trucks run fine and can pass our E-check here in Ohio.
So before you start buying sensors and other misc. parts , try the gear if you are getting a P1345 code. I was surprised at the wear because I religously used Mobil 1 and can only put the cause on the GM parts supplier.
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