Thread: LT1 problem.

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My son has a '95 LT1 camaro. It's stock other than a few bolt-ons. It has shorty headers, MDS ignition MSD 6AL(still opti -spark) mild cam. 6 speed. All the MSD stuff is less than a year old. The control box is under the hood. I've always thought the 6's were safe under the hood and the 7 series boxes should not be in the engine compartment. I think he plans to move the box under the dash as a precaution anyway.

We took the car to the track a week ago and the first run was fine. The next 3 runs it fell on it's face off the line, then about 1/2 way through low it would catch and run fine. It would then pull like normal every shift. At first we thought it was just the slicks bitting since we dropped the air pressure from 18 to 15 psi. But, every lap it would bogg no matter what RPM it left at. (I have a habit of leaving too hard and even I couldn't get it to not bogg off the line).

It literally takes 100' or more before it will wake up and from that point on it seems to run O.K. It would 60' @ 2.5 sec. to give you an idea how slow it was off the line. The 2 laps I made I had .0205 & .0156 R/T and leaving over 4g.

Also, if we let it cool off, it will run hard off the line once. Then when the temp comes up it's back to bogging. It just picked up this new habit a week ago. Jeff replaced the fuel filter today with no change. He also replace the coil with a new one & no change. Also has fresh plugs, gapped, and new Moroso plug wires.

Could it be a sensor acting up? if so, which one? Any suggestions would be appreciated.

Update.

Jeff replaced the knock module with one for an LT4.

He also (last couple days) has had the problem get worse, to the point it wouldn't idle at all. Running very rich. He replace both 02 sensors and replace the exhaust collector donuts by the 02 sensors with new ones. Took it out for a test and it runs much better but still not like it should. It still has a hesitation off the line. He still hasn't bought a fuel pressure gauge, that will probably be next on his list. Anytime I've had a lean condition it's been at high rpms, this happens at low rpms and straightens out at high rpms. In higher gears when the engine is lugging harder it has all the fuel it needs and pulls hard like it should.

Any other ideas? Jeff's gettin' frazzled.

Thought I'd throw in this picture of his camaro at the track.

Race gas?

Fuek level in tank???

Pump gas. full.

Vapor lock????shorty headers, residual heat under hood---maybe a defective fuel pressure regulator

Is CC, IL coal city?

Originally Posted by jerry clayton

Is CC, IL coal city?

Yup.

He hasn't checked fuel pressure yet. It's on the to do list. He's been running this combo for years with no major problems. I think he's ordering the diagnostic & editing software. That should help narrow down the problem. This car runs 14 flat on a good day. I think it should have mid 13's in it. The person he bought it from never tuned it after rebuilding with after market injection, cam, headers, etc. I think the ECU is confused with the new parts. It runs fairly good when it's cold, but runs bad when it's hot so it must be a closed loop problem some place. After guessing wrong a couple times, he's decided to get the software before buying any more parts.

Originally Posted by pro70z28

Any suggestions would be appreciated.

Ummmmm. Buy a 5.0 Mustang and go a lot faster??????








Didn't really think I could leave this one alone forever, did ya????

Originally Posted by Dave Severson

Ummmmm. Buy a 5.0 Mustang and go a lot faster??????








Didn't really think I could leave this one alone forever, did ya????

HEHEHEHEH, I see you haven't lost your sense of humor Dave.

Last year Jeff ran one of those Mustangs @ Eddyville's 1/8 mile track.

Smoked 'em 4 for 4.

Pat had a guy ride along with him in the Stude with a lap top and do a tune up on the whole system in his.... Can you do that in the kid's car?????

Sure beats guessing on which parts to swap out....?????

Yup. I think Jeff is ordering the software. That should make finding & fixin' the problem easier.

After this years trip to Eddyville I told Jeff. "Good thing that Mustang didn't show this year huh" Jeff is still trying to hit that 8.48 I ran back in the 70's. best he's run to date is 8.87. I think if he puts a good tune up in that thing it should beat my old time.

I told him he better hurry up & beat me, cuz' I WILL be gettin' the "Z" runnin' one of these days & then that LT1 will be out of luck.

Originally Posted by pro70z28

Yup. I think Jeff is ordering the software. That should make finding & fixin' the problem easier.

After this years trip to Eddyville I told Jeff. "Good thing that Mustang didn't show this year huh" Jeff is still trying to hit that 8.48 I ran back in the 70's. best he's run to date is 8.87. I think if he puts a good tune up in that thing it should beat my old time.

I told him he better hurry up & beat me, cuz' I WILL be gettin' the "Z" runnin' one of these days & then that LT1 will be out of luck.

Yuppers!!!!! Well, let's hope so anyway!!!!!!!!

Can't expect me to be a nice guy all the time!!!!!!

I'm LQQKin' forward to the laptop tune-up.

I'm finally moving on from points & carb.