1994, 6spd, lt1 engine problem
Thread Starter
Pro
Joined: Jan 2010
Posts: 661
Likes: 2
From: Ca.
1994, 6spd, lt1 engine problem
I have the chance to purchase a 1994 c4 that has 107,000 miles, 6spd trans. and a engine miss at 5000 rpm and up.
Is this a deal breaker, or an easy fix?
He says he just installed a rebuilt lt1 12,000 miles ago.
lt4 hot cam
ported heads
baer front brakes
aftermarket sway bars.
$5,900.
Is this a deal breaker, or an easy fix?
He says he just installed a rebuilt lt1 12,000 miles ago.
lt4 hot cam
ported heads
baer front brakes
aftermarket sway bars.
$5,900.
Safety Car
Joined: Aug 2008
Posts: 4,344
Likes: 48
From: San Marcos CA
If it runs ok at lower revs, it's probably an ignition problem. Maybe he went cheap and reused the old opti-spark cap and rotor or the sprk plugs/wires aren't the best. I had 77k mile spark plugs in mine with a new opti and wires (from a water pump repair. Dude tried to save $50 and a couple of hours labor to change the plugs because he heard the mid 90's GM cars had a 100k mile tune up (doh, 15 years is still 15 years).. Anyhow, after I put in new plugs it ran to 6 grand without missing.
Burning Brakes
Joined: Aug 2007
Posts: 917
Likes: 2
From: Charlotte NC
A miss at low rpm's that goes away with higher rpm's is a typical ignition problem caused by fouled out plugs/wires, or OPTI distributor.
The opti could be the issue but from my personal experience, A high rpm miss is usually from air, fuel or exhaust.
:clogged converter
:clogged up fuel filter
:bad/clogged fuel injector
:MAF (check codes)
:weak fuel pump/poor fuel pressure.
etc..
Also
Never trust anyone that says "New motor" without paper work and receipts to prove it. If he don't have anything to show other then his word, then he is most likely lying to you. People tend to keep receipts for auto repair when they are over $2000. At least for the warranty period.
If they lie about that imagine what they are not telling you.
The opti could be the issue but from my personal experience, A high rpm miss is usually from air, fuel or exhaust.
:clogged converter
:clogged up fuel filter
:bad/clogged fuel injector
:MAF (check codes)
:weak fuel pump/poor fuel pressure.
etc..
Also
Never trust anyone that says "New motor" without paper work and receipts to prove it. If he don't have anything to show other then his word, then he is most likely lying to you. People tend to keep receipts for auto repair when they are over $2000. At least for the warranty period.
If they lie about that imagine what they are not telling you.
Drifting
Joined: May 2010
Posts: 1,990
Likes: 2
From: Gaithersburg MD A member since 2007 but then the computer crashed and then the car crash loss of memory X 2
A miss at low rpm's that goes away with higher rpm's is a typical ignition problem caused by fouled out plugs/wires, or OPTI distributor.
The opti could be the issue but from my personal experience, A high rpm miss is usually from air, fuel or exhaust.
:clogged converter
:clogged up fuel filter
:bad/clogged fuel injector
:MAF (check codes)
:weak fuel pump/poor fuel pressure.
etc..
Also
Never trust anyone that says "New motor" without paper work and receipts to prove it. If he don't have anything to show other then his word, then he is most likely lying to you. People tend to keep receipts for auto repair when they are over $2000. At least for the warranty period.
If they lie about that imagine what they are not telling you.
The opti could be the issue but from my personal experience, A high rpm miss is usually from air, fuel or exhaust.
:clogged converter
:clogged up fuel filter
:bad/clogged fuel injector
:MAF (check codes)
:weak fuel pump/poor fuel pressure.
etc..
Also
Never trust anyone that says "New motor" without paper work and receipts to prove it. If he don't have anything to show other then his word, then he is most likely lying to you. People tend to keep receipts for auto repair when they are over $2000. At least for the warranty period.
If they lie about that imagine what they are not telling you.
Words spoken by someone who has experienced the "Trust Me" line.
Thread Starter
Pro
Joined: Jan 2010
Posts: 661
Likes: 2
From: Ca.
Thank you all for your information. I am going to check to see if there is a company that checks used cars, so there is not a gotcha.
I have a ZZ3 crate engine, but do not know what it compares to. L98? I could remove the intake and install the 94 intake and other parts, if the 94 engine is not good.
I have a ZZ3 crate engine, but do not know what it compares to. L98? I could remove the intake and install the 94 intake and other parts, if the 94 engine is not good.
Drifting
Joined: Dec 2007
Posts: 1,329
Likes: 17
From: woodbury new jersey
when i got my car it had a miss over say 3500 rpm. turned out my wires were garbage. had the engine running in the dark, and 3 of them were arcing like a mother. changed them out and problem was gone
Drifting
Joined: Aug 2009
Posts: 1,971
Likes: 243
If you have some mechanical inclination and the rest of car seems solid the price seems not bad.
My 94 developed a miss immediately after I bought it on the ride home. I figured a tune up was in order and replaced plugs, wires, coil and ICM - it was cured. It started missing again a few months after that and I narrowed it down to a bad MSD coil and a possibly faulty ICM (yes the parts I had just replaced a few months prior!). I decided to eliminate those two parts all together and went to an LTCC setup with LS1 coil packs and I haven't looked back since - stock opti 110k.
Mine was a low rpm miss mostly but it would also cut out in the upper revs as well - over 5k but only sometimes. At idle it was misfiring almost always and the tach was jumpy. Not to disagree with the above posters but I wouldnt rule out ignition just because it is only showing up at higher rpm. Plugs/wires are a good start to a tune up anyway. There are checks you can do on the coil with an ohm meter and most auto parts stores can test the ICM for free.
Good luck with your decision.
My 94 developed a miss immediately after I bought it on the ride home. I figured a tune up was in order and replaced plugs, wires, coil and ICM - it was cured. It started missing again a few months after that and I narrowed it down to a bad MSD coil and a possibly faulty ICM (yes the parts I had just replaced a few months prior!). I decided to eliminate those two parts all together and went to an LTCC setup with LS1 coil packs and I haven't looked back since - stock opti 110k.
Mine was a low rpm miss mostly but it would also cut out in the upper revs as well - over 5k but only sometimes. At idle it was misfiring almost always and the tach was jumpy. Not to disagree with the above posters but I wouldnt rule out ignition just because it is only showing up at higher rpm. Plugs/wires are a good start to a tune up anyway. There are checks you can do on the coil with an ohm meter and most auto parts stores can test the ICM for free.
Good luck with your decision.
Instructor
Joined: Jun 2002
Posts: 154
Likes: 3
From: San Diego CA
from someone that has been fighting high RPM misses, check the wires first. Also, watch the coil wire for arcing. I just put a rubber fuel hose over the coil wire where it rests on the coolant neck. that worked for me. (after replacing all the wires to correct various other arcing areas)
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