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 1994 LT1 dead...

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BrotherJohn

BrotherJohn

Posts : 14
Join date : 2017-04-26

1994 LT1 dead... Empty
PostSubject: 1994 LT1 dead...   1994 LT1 dead... Icon_minitimeTue Jun 08, 2021 1:28 pm

Greetings, all..

'94 Caprice has had nearly everything replaced in the last few years, trans rebuilt, new spark, a bunch of new sensors, new water pump in April...

It's been running pretty well, but with a thf thf thf thf thf thf thf thf sound that suggested a misfire, despite there being new plugs and wires.

Sunday, after a short drive, it felt like it was losing power. Getting off the line was making me very nervous in traffic. Up to speed, it seemed fine. It barely made it home, literally coasting in the driveway after doing 5MPH the last 100 yards.

Oil seems dirty but not foamy or discolored, and I still see green in the overflow tank. I was concerned a head gasket might have gone, especially given the loss of power combined with that noise. I can hear the fuel pump spinning up, and it turns and turns but won't kick on. Am I facing the same trouble [You must be registered and logged in to see this link.] is, or should I be looking elsewhere?
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goldwolfnhn



Posts : 214
Join date : 2019-07-11
Location : De Pere, Wisconsin

1994 LT1 dead... Empty
PostSubject: Re: 1994 LT1 dead...   1994 LT1 dead... Icon_minitimeTue Jun 08, 2021 2:38 pm

for the LT1's the only real problem with fuel pumps has been with after market units usually, but I would check fuel pressure first should be mid 30's I think to low 40's, but with my vehicles usually when I could hear the pump it wasn't a fuel issue.

Not sure if a bad fuel pressure regulator would cause a no start but that could be another possibility.

have you replaced the ignition coil? what about the ignition control module?

and just because your not losing coolant and your oil looks 'normal' doesn't mean there might not be a blown head gasket, it might have just blown out between cylinders.

a compression check I believe is usually the best way to find out if that's what happened, or using a leak detector, it can detect exhaust gases being released into the coolant. (had 2 vehicles come into the shop no problems other then overheating, both had blown headgaskets, as exhaust gases where getting into the coolant.)

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BrotherJohn

BrotherJohn

Posts : 14
Join date : 2017-04-26

1994 LT1 dead... Empty
PostSubject: Re: 1994 LT1 dead...   1994 LT1 dead... Icon_minitimeTue Jun 08, 2021 9:49 pm

Yessir, I've replaced the coil and ICM prior to the optispark being replaced last September, and I can't see any evidence that it actually overheated. In fact, an IR thermometer was reading something like 168 degrees at max. A burned gasket between two cylinders has crossed my mind. This car will probably kill me eventually. Thanks for your quick response, I appreciate having a universe of smart people to bounce ideas off of.
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Rev Bob



Posts : 376
Join date : 2016-05-24

1994 LT1 dead... Empty
PostSubject: Re: 1994 LT1 dead...   1994 LT1 dead... Icon_minitimeWed Jun 09, 2021 9:17 am

Blown head gasket would show up in other ways before power went to almost nothing. Basic trouble shooting. Check for fire at the plug, fuel to the injector, power at the injector. If it is all there, then a compression check would be the next step.
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Swaggerwagon

Swaggerwagon

Posts : 83
Join date : 2013-06-18
Age : 91
Location : Detroit metro

1994 LT1 dead... Empty
PostSubject: Re: 1994 LT1 dead...   1994 LT1 dead... Icon_minitimeThu Jun 10, 2021 2:18 pm

Does the car have cats?
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