need some help, please engine experts >>

[Craig 94 TA GT]

I am out of my mind. For all those who have been following my problem...
I just got a call from the engine shop saying that I have internal motor damage. "The motor will turn but only turn 1 way" ????? What does that mean???? He said that it's frozen. He said that I possibly threw a rod???????
How the freakin he!! is this possible? I only have 100k on the motor and it was running before. How could it have just threw a rod?? From running fine...to bad idle (yet excellent above 1k)...to not starting....internal damage??
I am going to go insane if it's true.

[Craig 94 TA GT]

Let me elaborate for those who aren't familiar with what happened....
1) Someone poured sugar in my gas tank.
2) It fouled up the plugs, fuel pump, fuel filter, and possibly the injectors and regulator.
3) It started having a bad idle...such as the videos I posted on the net...
Here's a quick video of what is was doing:
Bad Idle
4) It stopped running altogether and I had my pump and filter replaced, and my injectors cleaned. After this happened, I noticed that my fuel pressure (with key on "on" position) went from 43 psi to 0 in a matter of seconds.
5) It ran well top end, but idle was bad (although not as bad as the video)
6) It took a while to start every time, but started up with the bad idle.
7) All of a sudden, the car wouldn't start anymore. I noticed that when I try to start it, I can hear the fuel pressure leaking out somewhere (when I see the gauge drop from 43 to 0). I can hear it dripping, as well, when I try to start it, yet I see/feel no gas on the outside.
8) I did notice that once in a while, you turn the key and nothing would happen. Like the engine "froze". But, after a bit, it would try to turn over again. When I put the battery charger on "start" mode, it would still freeze once in a while, but I don't think it was making good contact (The terminals on the batt don't make good contact anymore). I was able to get good contact 1 time, and the thing kept trying to turn over and over, yet wouldn't start.
9) Now he says I have internal motor damage i.e. threw a rod.

I really appreciate anyone's advice.

[ws6drbob]

I just went back and read your other posts and i must say that that is a terrible thing to happen to someone. I wish i could tell you that it doesn't sound like a thrown rod but from all of the experience i have had with a few buddies that have blown motors that is what it would appear to be to me. I had a buddy whose car was running kinda rough and we were on our way to the shop to drop it off(i was following him to give him a ride home) and while coming to the highest part of a bridge that was about 3 miles away from the shop his car lost power and we had to pull off the rod. The car wouldn't start so he had it towed to the shop and once they got it on the lift they saw a rod thrown completely through the block. The only thing that makes me angry about your situation is that his engine blew due to the fact that he drove it rough daily whereas your problems arose to no fault of your own(I believe sugar in the gastank was the catalyst of your problem?). If it is a thrown rod i hope you get the car back with as little of a headache as possible.

[Craig 94 TA GT]

If it is internal damage, then most likely, the car will be totalled, if insurance covers it. However, if I had a thrown rod, why would a compression test show 130 all the way around...and wouldn't it start on 7 cylinders?? Why am I not hearing any noise, nor heard a noise from the mechanical damage? Doesn't make sense...

[ws6drbob]

I am no engine expert so i couldn't tell ya why it tested fine but i have only heard of a few cases where a car will still run with a thrown rod(I didn't think it was possible because all the rods are connected to a single crank and if one is locked up then the others should not be able turn as well) and i was only TOLD about them I never actually saw them in person. But maybe your car has been doing that very same thing but finally broke completely in a way that i locked up the engine.

[Jeff_in_Atl]

Originally posted by Craig 94 TA GT
If it is internal damage, then most likely, the car will be totalled, if insurance covers it. However, if I had a thrown rod, why would a compression test show 130 all the way around...and wouldn't it start on 7 cylinders?? Why am I not hearing any noise, nor heard a noise from the mechanical damage? Doesn't make sense...

I don't know what the definition of "a rod is thrown" but to me it means it is no longer connected to either the crank or the piston. If that is the case, the cylinder with the "thrown rod" will not move the piston. Therefore it will have 0 compression on it. If all cylinders show at least 130 PSI, I don't think it has a thrown rod.

Sounds to me like you have multiple problems. I'm wondering if the started has gone bad from all the use recently.

I'm also wondering if the injectors are not closing all the way (because of the sugar) and leaking fuel into the cylinder. This would definitely cause it to be hard to start. If you pull the oil dip stick, does it smell a little like gas?

I'm barely an amateur mush less an expert with GMs or sugar in the tank but I'm trying to help. I know what it's like to be frustrated. I still don't believe there is anything wrong with the motor.

[katman]

If I remember correctly you had the injectors cleaned or replaced, but what about the fuel pressure regulator? You say the pressure starts out OK and goes to 0. Could the regulator just be recirculating all the fuel back to the tank? If you threw a rod you definitely would have heard it and you wouldn't have even compression. Be leery of the shop!

[TraceZ]

Originally posted by Jeff 95 Z28
I don't know what the definition of "a rod is thrown" but to me it means it is no longer connected to either the crank or the piston. If that is the case, the cylinder with the "thrown rod" will not move the piston. Therefore it will have 0 compression on it. If all cylinders show at least 130 PSI, I don't think it has a thrown rod.

Sounds to me like you have multiple problems. I'm wondering if the started has gone bad from all the use recently.

I'm also wondering if the injectors are not closing all the way (because of the sugar) and leaking fuel into the cylinder. This would definitely cause it to be hard to start. If you pull the oil dip stick, does it smell a little like gas?

I'm barely an amateur mush less an expert with GMs or sugar in the tank but I'm trying to help. I know what it's like to be frustrated. I still don't believe there is anything wrong with the motor.

I agree. If you have compression in all 8 cylinders, you do not have a thrown rod. I would be very leary of the shop. Didnt they pull some crap earlier too? I think it is time to take it elsewhere, and cancel payment.

[Craig 94 TA GT]

Thanks for your replies...
I almost knew it couldn't be a thrown rod because I thought I would have heard it.
He took about 1 1/2-2 hrs to diagnose this. The thing he claims is that the thrown rod could be one of the problems but whatever the real problem is..."is part of the internal motor". Yet...I have heard no sounds at all, nor has it ever felt like it's been on 7 cylinders. It just idled bad...like it was starving.
BTW, the compression test was done a few weeks ago, but I have had 30-40 miles on it since then (before it stopped starting).
I really think it has something to do with my fuel pressure dropping from 45 psi to 0 in seconds. ALthough I would think it would still at least fire up...or run and die...I think the regulator is bad. But...would a bad regulator still cause it not to start? Even it the fuel passes through the return line, it still has to go through the rails and injectors because the regulator is on the back side of the fuel path. But I have no way of checking the pressure at idle/WOT, because it won't run period.
I will have a good talk on Monday with him. Any ideas on how to give him unrefutable evidence on why it isn't the internal motor?
Thanks....

[DJ Taso]

If you can, try and bring it to a performance shop specialist. He'll tell you what's wrong with it. Don't just bring it to any mechanic down the street. They will rape you.

[Craig 94 TA GT]

I agree with the idea...
this guy is different than the original guy I took it to (who changed the plugs + wires for $487 and threw away my TR-55s and 8 mm Spiro Pros w/ 15k).
The shop & mechanic who gave the diagnosis WAS good...WAS highly recommended...however, if he doesn't change his theory, especially after I talk things through, then he WAS my mechanic...and will be someone different. I know money is the root of all evil...so if he thinks he could score cash off the insurance by saying I need a new motor, then he should think again. They will total the T/A in seconds, and laugh at his need for $6-$8k for a new motor and install. If he thinks he will charge me that much, then he is out of his mind. I don't know the real story, but all I know is that an LT1 engine is not supposed to throw a rod by 100k. And, I floored the thing maybe once or twice in the last 2 years. I try to take very good care of her, as all we f-body owners do.

What I don't understand...this guy claims that the engine doesn't turn both ways...which is likely a thrown rod in his opinion. Firstly, could anything else cause this? (i.e. starter motor, flywheel, etc.). Secondly, is it supposed to do this?? Thirdly, would I hear a clanking or metal to metal sound when it's trying to start up?

[TraceZ]

Originally posted by Craig 94 TA GT
I agree with the idea...
this guy is different than the original guy I took it to (who changed the plugs + wires for $487 and threw away my TR-55s and 8 mm Spiro Pros w/ 15k).
The shop & mechanic who gave the diagnosis WAS good...WAS highly recommended...however, if he doesn't change his theory, especially after I talk things through, then he WAS my mechanic...and will be someone different. I know money is the root of all evil...so if he thinks he could score cash off the insurance by saying I need a new motor, then he should think again. They will total the T/A in seconds, and laugh at his need for $6-$8k for a new motor and install. If he thinks he will charge me that much, then he is out of his mind. I don't know the real story, but all I know is that an LT1 engine is not supposed to throw a rod by 100k. And, I floored the thing maybe once or twice in the last 2 years. I try to take very good care of her, as all we f-body owners do.

What I don't understand...this guy claims that the engine doesn't turn both ways...which is likely a thrown rod in his opinion. Firstly, could anything else cause this? (i.e. starter motor, flywheel, etc.). Secondly, is it supposed to do this?? Thirdly, would I hear a clanking or metal to metal sound when it's trying to start up?

I'd get a good battery and starter in it, get in cranking and do a compression test. I'm smelling BS.

[Craig 94 TA GT]

I was thinking about doing it myself...the only thing is that if the problem is the injectors/regulator, the insurance would cover it...or anything else fuel related. However, they said I'm not supposed to work on the car since I'm not a licensed mechanic. The inspector did take pictures of the motor, so I don't know if they would consider it tampering if I'm working on it myself...and possibly void all potential payments for repairs done.
I wish I had more $$$, but cash is limited now. If I did, I would do everything my d@mn self and say kiss my (_)(_) to the mechanics!!
Sorry, just extremely upset...especially since he called 15 minutes before closing for the weekend. Now I have to wait 2 agonizing days

[Joe 1320]

Ashop manual would be invaluable. This story is exactly why I do my own work. We'll help you diagnose all this, but picking up a manual is a must.

[Craig 94 TA GT]

I do have a Haynes shop manual, but is only adequate in detail. When it comes down to some stuff you need to know in detail, it falls short. What other shop manual brand is there (besides Chiltons...doesn't have that much more than the Haynes).