SPG

iTrader: (3)

As stated I have no DTC, but the car runs terrible. wont tickover, wont pull,

I have spark plugs that one bank look tan colored, the other bank are dark black, but not wet.

no codes

one o2 sensor that looks like normal curves
one o2 sensor that looks like it is erratic

have swapped both o2 sensors for the rear ones (dont use those in my application) .....no effect


stock plugs, 50 thou gap


this started after a 30 hot laps a track day, no missed shift, nothing mechanicaly sounding wrong

any suggestions befor eI start to tear into it

SPG

iTrader: (3)

tttttttttttttttttt

Jon5212

iTrader: (2)

Is it possible the car went into limp mode? I don't know if that will throw a SES light or not?

mikenews

iTrader: (9)

+1 for that

Jon5212

iTrader: (2)

Updates?

SPG

iTrader: (3)

Updates

I reflashed the ecu with an old backup tune, which seemed to clear up some of the issues, (the car runs now, but cant tickover till warm). but I am having difficulty tracking down why it wont run well

so far I have

cleaned all injectors (no effect and no debris found)

swapped all plugs from one side to the other, no effect
swapped plyg wires, no effect
swapped coils across, no effect
checked exhaust manifold temps, side with black plugs was 20 degrees colder than the other side, with all 4 cyls on that side reading similar

If i disconnect the rich bank coils while running, the engine still runs but stumbles
if I disconnect the other side coil whille running, the engine dies immediately

Tomorrow I will remove the exhaust and try running without cats, perhaps running rich for a while has blocked the cat with carbon deposit....is this a posibility.

I have hp tuners, so can scan this, I can see the o2 sensor looks different from one side to another, but this is the second o2 in a fewmiles, need to seewhat is causing the problem

can also see the STFT and LTFT one side are way different, 15% adjustments from stock. Never seen thesemove around more than a few % before.

thanksfor any ideas....... currently checking the integrity of the loom......damn there are a lot of wires to check!!

SPG

iTrader: (3)

OK checked the loop, pin by pin, found no irregularities.

swapped out the o2 sensor, which was a little dark and sooty, car runs better,but still not right.

I will see if i can get a scan tomorrow, and post a shot of the sensor

02SOMWS6

iTrader: (6)

how bout the crank or cam sensor? I had a crank sensor go bad that didn't kick anycodes and cost me 5 tenths in the 1/4 mile. Would run fine standing still but would spit and sputter when driving

andrew69_04

iTrader: (148)

Dirty MAF?? i just ran into that with my camaro. threw no codes but just ran like ****. cleaned the MAF and wow what a difference. maybe check to see if the little wire things inside the sensor are good and clean.

SPG

iTrader: (3)

think that with the clear difference from one bank to another this must be 02/fuel/coilpack related.

will check maf, cam sensors etc though

SPG

iTrader: (3)

maf cleaned, sensors checked, swapped another o2in, car runs, but as soon as it starts, LTFT and STFT start tomove one side

I cant post a scan here, but if you have hpt, you can see the post on the hpt site

http://www.hptuners.com/forum/showth...982#post103982

any suggestions much sppreciated

P Mack

iTrader: (6)

Are the LTFT and STFT going high or low on the side with the black spark plugs? Sounds like you could have an exhaust leak or something giving you invalid o2 readings, making you run rich on that bank.

2xLS1

iTrader: (25)

What the hell is tickover?

SPG

iTrader: (3)

Sorry

English for "idle"

you have hood, we have bonnet
trunk = boot
harness = loom
petrol = gas

sure there are many more !!

SPG

iTrader: (3)

bank 2 is going negative fuel trims, I "think" bank 2 is piston 2,4,6,8, piston 2,4,6,8 are the ones getting black

SPG

iTrader: (3)

checked the manifolds, could nip acouple up a little, perhaps 1/8 turn, but no more

also took rocker cover off, this has not been run for a couple of weeks, is this normal condensation, or a water leak.

also thought oil pressure was a little low, 30, not the normal 38 i normally see

any thoughts..............

SPG

iTrader: (3)

checked the cyl balance test on hpt

1 89
2 92
3 89
4 91
5 95
6 90
7 93
8 89

this is an average of 3 readings for each cylinder, none of them varied more than a couple of pointsfrom each other for each cylinder

started a compression test, did
1 220
3 230
5 225,

then the bloody comp gauge stopped holding pressure, couldnt see a thing.

went and bought another, but as the plugs were all out, and it took acouple of hours or so to get a replacement, the test was definately "warm" not "hot"


results.....

1 200
2 115
3 240
4 130
5 220
6 145
7 210
8 125

this was with all spark plugs out, and yes rechecked a couple each side to make sure I did not misread the gauge......

Think I see a pattern............

SPG

iTrader: (3)

for an update go here
https://ls1tech.com/forums/generation-iii-internal-engine/791902-fubar-d.html

bigtymn

im no expert but it sounds like you got some bent pushrods
ls1 car are known for this!!! bad shift or a miss shift or a over rev
ive seen it a couple times and its happend to my own ls1
it a cheap fix

bigtymn

im a little slow you will have to not mind me