• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

so many possible problems.

S

swany

New member
so backround i put a l67 from a 98 bonneville in my 97 grand prix gt ( yes i know that i have the crappy tranny) i have installed a few things such as ported exhaust, ceramic coated crossover pipe throttle body spacer etc. i have aa pcm through zzp thats seems to be an o.k. tune

im slowly trying to troubleshoot and discover the problem but unsure if any one else already knows the answer. the car stalled out and i found fuel in oil. changed oil to avoid bearing wash and checked fuel pressure regulator and it seemed alright. two days later stalled again i got it started again with some difficulty and it was clanking from the front of the motor by cylinders 1 and 3. as i inspected it belts chirped and motor locked up we trailered it and looked at it later. motor was cranking again and it runs again smoothly. horrible clanking from cylinder 1,3 area. i checked plugs and only cylinder 3 smelt like it was doused with gas so possible flooding. checked compression and had about 150 on all cylinders except 127psi on cylinder 3.

im thinking possibly injector tip broke off in cylinder 3, timing jumped, or wristpin or rod on clyinder 3.

all thoughts and sugestions are encouraged and gladly accepted
thanks guys
 


P0300 is multiple misfire IIRC. I'd do what FFDP says and see if the miss follows. That clanking sound isn't good. I'd bet you chipped a piston or broke a ring on that cylinder. Injector tip is plastic, timing on a stock chain RARELY jumps (about as often as a Head Gasket failure), and the wrist pins hold up fine, its the piston and bearings that usually take a beating.

Are you running 91+ octane in this car? What type plugs are you running? Is there any way you can put a stock tune back on this and eliminate the ZZP one? They usually run rich so you don't blow it up. Also, are you running the stock 3.8 pully on the S/C or did you drop pulleys?
 
Timing shouldn't be able to jump.

The excessive fuel is your tip. Likely a bad injector or the plug isn't firing. Check for both. Have you checked oil pressure when warm?
 
hey i pulled the head and discovered parts of a ring in cylinder 3, im just wondering if you guys think that will be my only problem. it explains the loss of compression and im planning on picking up a new coil pack for #3 is there anything else i should check on this as i rebuild? thanks for the answers so far
 


Why pick up a coil pack for #3 if you broke a ring? That bottom end is trash at this point. Probably scored the cylinder wall while it was bouncing around in there. Any damage to the valves on that head? IMO you're better off getting a low mile longblock and swapping it in using your accessories/wiring, etc. And no, you cannot just take out that piston and replace the ring(s). Once you remove the rod cap you will probably have to put new bearings on that rod, which may or may not match up thickness-wise since the new ones are, well, new and the rest is worn in. Also the rod bolts are TTY and not reuseable.

Still never stated what plugs you were running or octane of fuel. I'd get it back together and get a REAL tune, not a canned ZZP one. And get an Aeroforce scangauge and a wideband in there if you don't already have one to monitor things like KR and whatnot so you don't have this happen again.
 
No, what I am saying is he needs to get it checked/scanned and re-tuned by ZZP if need be. Does he have a way to scan for issues? Without that he is just assuming everything is fine and I don't want him to eat another motor.
 
to answer your questions i was running 91 octane at all times, but centured out of town and had to put in 8 gallons of 87 (which pissed me off, and i should have known to pack some octane booster) im running ac 41-101 plugs my pulley is a 3.4 i had cai and some exhaust work done to alleviate some knock... plans thus far i have l67 back out starting to put the l36 back in ( still in perfect running condition) ill rebuild the l67 completely and also give me time to rebuild/upgrade a 4t65e that i picked up for little to nothing..

when i put the motor back in ill get my pcm reflashed through zzp, install a wideband, and i know a guy in south dakota ill pay a visit to him to get car properly tuned when i get the money. im currently in process of restoring a 72 toyota celica st and droppng a 4age into it.

any suggestions on internals as far as companies and quality stuff?
 
You must log in or register to reply here.
Back
Top