dave70

iTrader: (2)

02 Firehawk with a STS kit at just 5lbs all stock other than 42lb inj. valve springs,pushrods and 3200 vig converter. All the other cyl. looked great just the #5 looked as if it went lean for some reason? Anyone ever had this happen? I need to try and figure this out b-4 the engine goes back together as i don't want it to happen again. If the tune was off why just the #5 and not all the cyl.? I thought the # 7 was the first one to go most of the time. Thanks guys.

EPP

iTrader: (22)

It usually is #7 first, but we have seen #5 goes first before. What kind of a tune did you have in there? Bob

dave70

iTrader: (2)

From what the tuner told me the A/f was 11.5 and timing was 16 deg. On the dyno the car would never pull past 4700 so the springs were installed but did not help.So the tune was never complete. He took it on the street and maybe made one hard run with it. that's when it happened started blowing oil from everywhere. The tuner didn't figure out what was wrong with it. He is going to take it to another local tuner when it is back together Do you think the fuel pump was maxed out and that was just the last cyl. to get fuel and then went lean?

DeltaT

iTrader: (5)

Yeah, you can't really make any hard runs at all until the tune is damn safe (rich and lo-advance). Datalogging is needed to see what is happening. Too bad he blew it and probably won't pony up a dime.

Jim

dave70

iTrader: (2)

Well I'm not blaming the tuner. Just trying to see what the problem is so it doesn't happen again.The tuner is top notch i just don't understand why he could not get a better grip on what was going on. So i posted on here to see if anyone had any ideas. I have some pics I'll try to get up tomorrow night.

RooRnZ28

iTrader: (14)

are you running an intercooler?

crashly

i donot know what a sts kit is...
but
if it is fuel injected, then why not that injecter faulty?

if the injected faulty, and restricted.. it will burn up the plug and if hot enough, will torch the piston and the exhaust valve will be overheated.
same as us mechanical injected boys... if we have a block nozzel, booooom , THAT CYLINDER LEANS OUT.
Can you test the injecters , or put them on a flow bench to test flow volumes?

if the fuel pump was maxed, and the whole system would go lean, then the rear 2 cylinders should have shown lean cylinders.., if the efi fuel rails were feed from the front...

what does the spark plug " say"
post a picture of it...
has the earth electrode burnt of??
wash the spark plug with white spirts, and see if the "cad plating" is burnt off the base circle.
compare it to a new plug, straight out the box, better still post a side- by - side pic of new and # 5 plug...

does this engine have coil packs?
could that cylinder spark have been advanced?

heaps of reasons, not necassery the tuners fault, BUT could be too...

cheers
ash

LASTLS1

iTrader: (7)

Dyno first then beat on it. Make sure you make the right decision with the tuner you use.

WhosNXT

The car all stock but for the sts kit, 42lb injectors, springs and stall. So yes it is fuel injected and has coil packs. I do not think either of those played a role in this though. It sounds like more of a tuning issue and #5 was the first to pay the price. Most likely all cylinders where running lean. I would take it to a good dyno shop to get it tuned. Then go for a street tune. Its not good to run hard while is leaning out, get it on the dyno then go for a spot on street tune.

dave70

iTrader: (2)

Thanks for all the help guys. I don't think the tune was the problem. The other 7 cyl's all looked pig rich.That goes with what the Tuner was saying. The #5 however is blasted clean No carbon at all the plug shows lean but is not burnt The electrode is not melted. I'll try to get pics up of the piston And plugs. Right now I'm leaning towards the injector not flowing like it should for whatever reason. it could be something in the harness or trash caught in the injector or maybe even a computer problem. If anyone has any more ideas feel free to post them up. Thanks guys!!!!

John_D.

iTrader: (2)

If that cylinder was getting water, the plug will be clean.

Is the piston melted, or is it broken?

dave70

iTrader: (2)

It's melted. All the ring lands so the rings broke and scored up the wall. Also i have to check the turbo for damage. I found piston parts and ring bits in the oil pan.

John_D.

iTrader: (2)

Whew, that's a pain. I had 3 stock pistons let go, three years ago. When I found bits of them in the intake, I knew they had gone out the exhaust for sure.

Hopefully the turbo is ok. Good luck with it!

67Firebird455

iTrader: (27)

I had #2 in mine go... nuclear meltdown. Blew a pretty good section out of the top of the piston.

dave70

iTrader: (2)

This one melted through the ring lands in the front of the piston the top looks melted and the rings and lands look broken. I'll try to get some pics up. i'm trying to see if anyone local flow tests injectors.