Can't get rid of 301 code

[buffercat]

Ok 2005 Impala, car runs great but keeps tripping on engine light and will flash occasionally. We have replaced plugs, wires, injector, switched coil packs which code did not follow to other cylinder. When I hook LED light to switch below coil pack and start car light flashes, have 13 volts coming into coil pack. Need some help before spending buddies $$$ in the wrong area. Ideas ?? Thanks

P.S shows 2 codes PO301 and 2nd is PO301 P what is the other P for ??

[oldblu65]

Originally Posted by buffercat

Ok 2005 Impala, car runs great but keeps tripping on engine light and will flash occasionally. We have replaced plugs, wires, injector, switched coil packs which code did not follow to other cylinder. When I hook LED light to switch below coil pack and start car light flashes, have 13 volts coming into coil pack. Need some help before spending buddies $$$ in the wrong area. Ideas ?? Thanks

P.S shows 2 codes PO301 and 2nd is PO301 P what is the other P for ??

www.obd-codes.com/p0301

[autojoe]

check compression on number one cylinder......burned valve?carbon buildup?maybe a vacuum leak near cylinder one.....

[GMCustomerService]

Good morning,
I understand wanting to be efficient with the use of resources. Have you been having this work done with one of our dealerships, because I would like to follow up with them on these repairs if so. Send me a private message with the last 8 digits of your VIN and the name of your dealer, and I'll contact them.

Best,
Sarah
GM Customer Service

[buffercat]

Sarah, I used to do mechanical this is a friends vehicle. I believe all work has been at the dealership except for a resonator that was installed a month earlier to the light coming. Finding that hard to be the cause but ....He asked me to look at it, car runs smooth, we did the tests listed above, I will do compression test etc but car is maintained to the max and is not driven hard and runs perfect. I don't think 3.8's are prone to this problem. I will verify all work that was completed at dealer and if he would like to go that route with you I'll message info to you. Thanks for your interest. Paul

[j cAT]

Originally Posted by buffercat

Sarah, I used to do mechanical this is a friends vehicle. I believe all work has been at the dealership except for a resonator that was installed a month earlier to the light coming. Finding that hard to be the cause but ....He asked me to look at it, car runs smooth, we did the tests listed above, I will do compression test etc but car is maintained to the max and is not driven hard and runs perfect. I don't think 3.8's are prone to this problem. I will verify all work that was completed at dealer and if he would like to go that route with you I'll message info to you. Thanks for your interest. Paul

I would check the injector, also the compression . #1..

[autojoe]

already replaced the injector.

[rkvons]

Originally Posted by autojoe

already replaced the injector.

What about the wire to the injector?

[j cAT]

Originally Posted by rkvons

What about the wire to the injector?

thats what I was talking about . swaping injector is not the complete test..wiring/ground etc..

also no compression readings so far.. not a common problem.

[buffercat]

Sorry for not posting back, we replaced the ignition control module, erased the code and was good for 2 days now light is back on . Compression test was 180-185 in all cylinders on this bank, not a issue. I did unwrap the harness to check wires all looked good, this is being a occasional mis-fire so it's being a pain to track. Only 2 things left is I may do a injector swap between #1 & 3 to see if it travels and go deeper into the harness.
P.S Sarah yes some work was done at the dealer but they where chasing as well and was costing him to much($800 to date) by trial and error. They did plugs, wires, and a fuel injection/body cleaning with no improvements, he had it back 4 times I believe. I will send you vin etc later. that being said I am not saying the dealer is having trouble but they are doing the best they can with the tools at their disposal. GM's (all manufacturers) do not have the capabities to pinpoint a problem , only send you in a specific direction. This is not only frustrating for the customer and expensive but also for the tech doing the job, so they end up doing the trial and error method hoping they will hit the problem.

[buffercat]

UREKA !!!!!! Swapped injectors and finally got a misfire on #3 going to order another new injector and problem should be solved. Should this not have thrown a 200 series code for the injector ?

[Tech II]

That code will set if there is a "circuit" problem.......it won't set if there is a flow problem.....

[j cAT]

Originally Posted by buffercat

UREKA !!!!!! Swapped injectors and finally got a misfire on #3 going to order another new injector and problem should be solved. Should this not have thrown a 200 series code for the injector ?

In post #1 by you it is stated #1 injector was replaced. so my question is who replaced it and where was this injector purchased ?

also how come the dealership could not figure this out after several expensive attempts ?

[buffercat]

I do not know where he purchased it but it was a mail in order so no refunds I\m assuming. it was not installed by the dealer. As for the dealership I cannot speak for,, they kept leaning towards plug/wire, but their next steps would have been replacing what we swapped. Even if they swapped parts the labour alone would have been quite abit at around $80 hr. Any electrical he would have to absorb as soon as it was installed. I will install a new one and post when all is good. I would like to thank eveyone for there help and that some of this may help others if they run into something similar Paul

[j cAT]

Originally Posted by buffercat

I do not know where he purchased it but it was a mail in order so no refunds I\m assuming. it was not installed by the dealer. As for the dealership I cannot speak for,, they kept leaning towards plug/wire, but their next steps would have been replacing what we swapped. Even if they swapped parts the labour alone would have been quite abit at around $80 hr. Any electrical he would have to absorb as soon as it was installed. I will install a new one and post when all is good. I would like to thank eveyone for there help and that some of this may help others if they run into something similar Paul

IF you could at some other time find the injector supplier it would be good.

still the dealership could not figure this out . this just adds to my belief that when the vehicles are past warrantee age the dealership is to be avoided..COSTS TOO DAMM MUCH !

GOOD LUCK TO YOUR FRIEND WITH THIS .