nlehrenreich

I have a 94 caprice wagon with the LT1. It has 205,xxx miles on it. Recently it has been having some running issues. When its cold it starts up and runs just fine, it also seems to start and run just fine if its at operating temperature and you shut it off and restart it again after a short time(like running into the store for milk). But if it cools down to say half way between operating and cold, it will idle rough, sometimes die, and sometimes backfire. It also seems like it doesn't want to rev up sometimes. If its running crappy and I let it run for a few minutes, sometimes with a little throttle in park or neutral it seems to fix the problem and it will run just fine after that until I shut it off and let it cool a bit again. I am running out of ideas on what it could be. Also there are no check engine lights, my change oil light just came on but that one is pretty self explanatory. I just changed the spark plugs(Bosch platinum +2) and the wires. Also cleaned the MAF sensor with MAF sensor cleaner. Anybody have any ideas on what could be wrong? Thanks in advance for your input.

POPIMPIN CUSTOMS I.N.C

opti can be going bad and have you changed spark plug wires lately? also could be a bad fuel pump change your in line fuel filter, its behind the driver rear tire its like $10 at the parts store

__________________
4 B BODIES
2 SOLD CAPRICES
1995 9C1 UNDERCOVER CAR WHITE ON IMPALA SS'S muff delete/ hollowed cats / I.N.C. REP TILL I DIE
1991 CAPRICE CLASSIC 350 160,000 CUSTOM 20'S STOCK 2 TONE
1991 caprice 305 payed $600 sold 4 $1200
1965 OLDSMOBILE STARFIRE 425 BIG BLOCK 375+- HORSES SMASHES ON FORDS

nlehrenreich

Well I finally had some time and a good enough day to get out there and work on it. I changed the fuel filter (and the oil while I was at it.) There seemed to be little change. It does still pop out the intake and hesitate. Should I just break down and buy a new opti or could it be something a little simpler like fuel pump or injectors or something fuel related? Any help is greatly appreciated.

POPIMPIN CUSTOMS I.N.C

well heres my 2 cents
every chevy motor from like 91 on had crappy fuel pumps that should be replaced about 100,000 or when they crap on u around 100,000 i dont think thats your problem but for $100 its way cheaper than a new opti or opti cap and rotor they only other cheap fixes i can tell you is replace the pcv valve ( driver side by intake) and a 85 egr valve might need to be replaced both of these get gummed up with carbon and on a 200,000 mile motor like mine ive replaced everything but the egr and fuel pump but i need to do both

like i said these are cheaper fixes b4 u decide if you need an opti i have 240,000 on my car and my opti was ok ( not sure if it was replaced by police dept that had it though) it didnt look ok though

so let me know since im the only person answering your question

__________________
4 B BODIES
2 SOLD CAPRICES
1995 9C1 UNDERCOVER CAR WHITE ON IMPALA SS'S muff delete/ hollowed cats / I.N.C. REP TILL I DIE
1991 CAPRICE CLASSIC 350 160,000 CUSTOM 20'S STOCK 2 TONE
1991 caprice 305 payed $600 sold 4 $1200
1965 OLDSMOBILE STARFIRE 425 BIG BLOCK 375+- HORSES SMASHES ON FORDS

Gregg-O

Get those bosch plug's outta there !! Well known to run like shit in these car's. Could possibly be the ECT sensor on the front of the WP. But I would still get rid of those plugs before you do anything else.

retirednak

When is the last time you did a fuel pump? Hook a gauge up and check fuel pressue.

__________________
'96 Caprice LT1 38K miles,Home plate/First base delete,K&N FIPK,MagnaFlow Exhaust, SStreetlights,
Custom tune by pcmforless.com

nlehrenreich

I hooked a fuel pressure gauge up to it yesterday, the schrader valve up on the fuel rail on the back of the engine. With the key on and not running it put out around 10 psi, which I thought was low. Then with it cranking it was at about 20 psi but it fired right up. I thought the LT1 needed somewhere around 42psi to run? Nonetheless I've kinda decided to stop kidding myself and just buy a new optispark and get it over with, or should I just replace the fuel pump first and see if it helps? I hate not being able to drive my wagon, I'm forced to drive a FWD 3.8L Bonneville back and forth to work and it is no where near as fun to drive.

Moby

I know you might think this is a stupid idea,but have you tried injector cleaner? What gas are you running in it?
Have a 95 caprice classic/lt1 wagon.thought i'd save a little money using regular unleaded and ran like crap untill i used fuel additive and went back to high test.couldn't get it to run right at all !! Had to keep pumping the gas to get it to run good enough to drive.once i went back to high test never had a problem since.
Cheapest way to problem solve ,if it works.

Good luck,moby1995

nlehrenreich

I only run 93 octane gas. Well I finally fixed it. I did both the Optispark and fuel pump. I did the opti first and it seemed to have little effect, but the old opti just looked like it was about dead anyway. Also changed out the serpentine belt while I was in there. Then I did the fuel pump the next weekend and like that it was back to its old self. I'm even getting better fuel economy now, probably because its actually burning all the fuel lol. Thanks to everyone who added their input in helping me figure this out.