firebird99

iTrader: (2)

Ok so my car keeps throwing codes and i have replaced most of them and no matter what about 15-20 miles later the check engine light comes on and the codes come back and along with the car running like crap it says i have 36degrees of timing at idle and 40 at wot now is there any way to know other than having to buy another computer to see if mine really is bad?

1.Two cylinder missfires codes
2.Two knock sensor codes
3.Tps sensor code
4.Maf sensor code
5.WAY TO MUCH TIMING

The maf and the tps have been replaced TWICE and i was going to do the others but i thought maybe there might be more to it then that so im waiting for some input before i ****** off the intake.Please help guys my car started doing this the very first day of the 2011 power tour and has been doing ever since but the weird part is as long as i keep it below 4500rpm it runs fine and gets 26mpg on the highway so it sucks because i have to baby it everywhere i go and its getting old but i did finish the entire tour so i did get a little lucky i guess

LS1-450

iTrader: (33)

What do the codes say? Do the TPS & MAF say sensor circuit low input? What's the # of the knock sensor code? Is it a P0325 or even a P0326?

sjsingle1

iTrader: (1)

the knock sensors sit in a water bath and rust.............the wire harness corrodes from the water too

sjsingle1

iTrader: (1)

LS1-450

iTrader: (33)

Haven't heard back from you. So, will reply based on what I thought you were gonna say.

Usually, a circuit low input to any 5v. reference user is an indication of a bad or failing PCM. So, if the MAF & TPS are sensor circuit low input codes, I'd look into a re-built PCM. The same may be true of the 2 Knock sensor codes listed. Either of these in conjunction with "circuit low input" codes would strengthen the case of a failing PCM.

P0327 & P0332 are Knock sensor low output codes. Either or both of these codes would indicate bad knock sensor(s) or sensor wiring. Possibly due to the condition noted in the reply above this one. However, if the knock sensor codes are the P0325 or P0326 (noted), the PCM is a good place to look. Especially, if these codes appear w/ the MAF & TPS codes...as stated.

W/ electronics, nothing is absolute. Usually, have to fix the issue through process of elimination.

89 formula350

iTrader: (8)

really??? PCMs rarely fail a low 5v ref is almost always a wiring issue. poor terminal contact (checked using a drag test) or any of the actual wiring to the sensors. a simple schematic and a few points of access checks will lead you to the failure

firebird99

iTrader: (2)

I don't know the exact code numbers just the codes themselves and my car is an hour away at my dads shop with the tranny out so I can't check for a little while I just know I'm tired of the car running like crap but I don't want to keep replacing sensors if it's the computer

LS1-450

iTrader: (33)

Yes, really. Those of us of whom have actually experienced the condition & resulting failure have noted such.

jimmyblue

iTrader: (11)

Start with the basics. Get yourself a usable voltmeter (Harbor Freight
flyers have a coupon for free ones) and start checking power and ground
at the sensors.

ENG SEN fuse could be blown. Quit swapping parts and get smart about
debugging.

89 formula350

iTrader: (8)

never mind I know better

southsidecox

iTrader: (11)

wow!! looking at those knock sensor pics you would think people at gm might have a clue on how to prevent that,looks like im going to have to prep mine with something before assembling my short block,i wonder if you coat them with something its going to affect their sensitivity?