P1345 P1351

[Octane Art]

Hey All,
I am completely baffled on these CEL codes p1345 p1351. I have a 96 C1500 5.7 auto with 211k on the truck. I bought it because it needed a new transmission. I got it home and proceeded was giving it a tune up plugs wires cap and rotor. the previous owner had use a drywall screw to hold the cap on and stripped the torq screw on the back side. So I bought a new delphi distributor delco ignition module coil and crank trigger. With not knowing the history of the vehicle I figured that would eliminate future issues with the ignition system. After installing the distributor got the p1345 and 1351 codes because it needed to be timed correctly. sent it to a buddy's shop got the truck timed and it ran great. drove it for a couple of weeks with no issues to put the mileage on to get it ready to smog it here in CA. it had a small exhaust leak at the collector on the drivers side so I had to get that fixed before smog testing. Previous owner broke and ear off the collector and booger welded the bolt and the bottom of the crossover pipe flange so i had to cut the pipe below the O2 sensor to pull the manifold and the EGR pipe out in one piece because I couldn't get them apart after 210k. I got the new exhaust manifold on and a new o2 sensor for the muffler shop to install and make a new crossover pipe. On the way down to the shop the truck backfired out of the throttle body and began to run like crap and the check engine light came on. I limped it to the shop had the exhaust fixed new O2 sensor installed. Picked the truck up and it was running fine. I got half way home and it back fired out of the intake again and began to run like crap. Just short of home the fuel pump died. This could have been the issue from the start but I had tested the fuel pressure and it was normal could have been and intermittent problem prior to failure. I tested the pump and circuit and figured the pump was bad. Put in the new fuel pump and filter. I fired it up and it idled beautifully but under load it run runs like crap and backfires out of the exhaust and intake. the same codes are present P1345 and P1351 the distributor hasn't been touched or moved nothing on the passenger side was messed with after the truck was running great. Any ideas would be helpful.
Thanks In advance
Greg

 

[Schurkey]

Connect a scan tool, look at the crank sensor/cam sensor signal alignment. Should be within 2 degrees at ~1100 RPM.

If the engine backfired when there was no exhaust system connected to the left exhaust manifold, I'd be tempted to clear the codes and see what comes back.

If they reappear, follow service manual diagnostic procedures for those codes. Download the service manual set from the links in the Sticky Threads part of this sub-forum.

 

[Casey916]

Hey All,
I am completely baffled on these CEL codes p1345 p1351. I have a 96 C1500 5.7 auto with 211k on the truck. I bought it because it needed a new transmission. I got it home and proceeded was giving it a tune up plugs wires cap and rotor. the previous owner had use a drywall screw to hold the cap on and stripped the torq screw on the back side. So I bought a new delphi distributor delco ignition module coil and crank trigger. With not knowing the history of the vehicle I figured that would eliminate future issues with the ignition system. After installing the distributor got the p1345 and 1351 codes because it needed to be timed correctly. sent it to a buddy's shop got the truck timed and it ran great. drove it for a couple of weeks with no issues to put the mileage on to get it ready to smog it here in CA. it had a small exhaust leak at the collector on the drivers side so I had to get that fixed before smog testing. Previous owner broke and ear off the collector and booger welded the bolt and the bottom of the crossover pipe flange so i had to cut the pipe below the O2 sensor to pull the manifold and the EGR pipe out in one piece because I couldn't get them apart after 210k. I got the new exhaust manifold on and a new o2 sensor for the muffler shop to install and make a new crossover pipe. On the way down to the shop the truck backfired out of the throttle body and began to run like crap and the check engine light came on. I limped it to the shop had the exhaust fixed new O2 sensor installed. Picked the truck up and it was running fine. I got half way home and it back fired out of the intake again and began to run like crap. Just short of home the fuel pump died. This could have been the issue from the start but I had tested the fuel pressure and it was normal could have been and intermittent problem prior to failure. I tested the pump and circuit and figured the pump was bad. Put in the new fuel pump and filter. I fired it up and it idled beautifully but under load it run runs like crap and backfires out of the exhaust and intake. the same codes are present P1345 and P1351 the distributor hasn't been touched or moved nothing on the passenger side was messed with after the truck was running great. Any ideas would be helpful.
Thanks In advance
Greg

I can't find the p1351 code Esther had it At two shops they can't figure it out I've had my either I've had my card laid up for almost a year now my registration is almost due again and I still have not had this dang code fixed and figured out can anyone help me too

 

[Schurkey]

I can't find the p1351 code

WHAT VEHICLE???

Download the service manual set for your vehicle from the links in the Sticky section of this web site. All the codes, and the associated diagnostic procedures will be listed in the manual.

Esther had it At two shops they can't figure it out

I don't know Esther. Tell her that the "shops" she's going to are worthless, and don't go there again.

I've had my either I've had my card laid up for almost a year now my registration is almost due again and I still have not had this dang code fixed and figured out can anyone help me too

Proper sentence structure, punctuation, and grammar are important communications tools.

 

[Octane Art]

Finally just getting back to the truck. its a 96 c1500 5.7 Silverado trim. My wife has been dealing with a few health issues, so the truck has been on the back burner. I have a coolant leak leaking into the drivers side of the engine. There is a small puddle forming at the exhaust tip on the drivers side after running for 5 mins or so. Its been converted to dual exhaust all the way back to the tail pipes. I know that the intakes leak on these engines as well as the head gaskets. Truck runs fine until the engine comes to operating temperature and the thermostat opens, pressurizes the cooling system and it begins to misfire and back fire out the exhaust. I am going to rent a coolant pressure tester from Autozone to see if the intake is leaking. If it is I am am probably going to change the head gaskets out as well if i am that far into it. The engine has 214k on it. My question at this point which head gaskets would you recommend? The Fel-Pro re-torque variety or the non re-torque? Thank you!

 

[Schurkey]

I believe I'd be VERY tempted to use the plastic- (elastomer-) coated steel shim gaskets. Inexpensive, no need to re-torque (although I'd probably re-torque anyway) and they improve both compression ratio and squish/quench. Prices have doubled since I bought mine. FJB.

MrGasket and Fel-Pro both make 'em.
www.summitracing.com/parts/fel-1094

Fel-Pro 1094 Fel-Pro Performance Head Gaskets | Summit Racing

Free Shipping - Fel-Pro Performance Head Gaskets with qualifying orders of $109. Shop Head Gaskets at Summit Racing.

www.summitracing.com

www.summitracing.com/parts/mrg-1130g

Mr. Gasket 1130G Mr. Gasket Head Gaskets | Summit Racing

Free Shipping - Mr. Gasket Head Gaskets with qualifying orders of $109. Shop Head Gaskets at Summit Racing.

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Some will say that you'd need new headbolts, too. That's not what the service manual says, though.

If you have the intake apart, consider installing an electronic-injector upgraded spider.

 

[Octane Art]

"If you have the intake apart, consider installing an electronic-injector upgraded spider."
Is that the MFI spider? I also have to look into the Kommi law here in ca if that is legal to do or not. Do you have a part number for the upgraded spider?
Thank you

 

[SableSlayer]

Finally just getting back to the truck. its a 96 c1500 5.7 Silverado trim. My wife has been dealing with a few health issues, so the truck has been on the back burner. I have a coolant leak leaking into the drivers side of the engine. There is a small puddle forming at the exhaust tip on the drivers side after running for 5 mins or so. Its been converted to dual exhaust all the way back to the tail pipes. I know that the intakes leak on these engines as well as the head gaskets. Truck runs fine until the engine comes to operating temperature and the thermostat opens, pressurizes the cooling system and it begins to misfire and back fire out the exhaust. I am going to rent a coolant pressure tester from Autozone to see if the intake is leaking. If it is I am am probably going to change the head gaskets out as well if i am that far into it. The engine has 214k on it. My question at this point which head gaskets would you recommend? The Fel-Pro re-torque variety or the non re-torque? Thank you!

Pull your intake manifold and check the gaskets. They're prone to fail and they cause all kinds of problems. Replace them with the felpro metal set