Vinscully50

I made a thread the other week about my car not starting properly because of a clicking sound.

I ended up taking my car to a local shop. One that was considered reputable by a few people I know. They told me the not starting problem was caused by the distributor being loose and the car out of tune. They fixed the distributor and adjusted the tune. The car runs much better in idle but as soon as they put it in gear it stalls.

Now what bothers me about the shop is that have had the car since last Friday and figured out the distributor on Tuesday. They haven't figured out what's causing the stalling problem yet. I know one other shop that's about 30 miles away that I do trust but I didn't go to him since people told me this shop was good and even through AAA it would have still been about an $80 tow.

Does it seem reasonable for a shop to take almost a week to figure out a stalling problem? Perhaps they just aren't experienced enough with TPI cars (A lot shops aren't, when I had my problem that ended up being my fuel sending unit, a couple of shops rejected my car because of the TPI. One offered to convert to Carb for $1000 or so and said the TPI is junk). They do call and give updates and seem nice but might not have experience with the TPI system. Perhaps I should have it towed from that shop to the other shop I know.

What would cause a TPI to run fine in idle but stall when put in gear?

Update:

There is an update in a post below.

TylerSteez

iTrader: (3)

vacuum leak is the usual culprit. min air idle speed adjusted too low could also cause it.

whats your fuel pressure looking like?

Vinscully50

I'm not sure. I'll have to ask.

Do you think it's bad if a shop has had the car for almost a week and it's simply a vacuum leak that they couldn't figure that out? I am assuming vacuum leaks should be easy to check for right?

TylerSteez

iTrader: (3)

vacuum leaks are pretty easy to check for which makes me wonder if they have already ruled it out or not, have they gave you any updates on what theyve checked on the car so far? maybe they're backed up with work and haven't had the time to mess with the old TPI car in the shop yet.

Vinscully50

I know before they found out about the lose distributor they checked all of the electronics and ignition parts. Today they said they were going to check out the MAF sensor.

I'll ask them what they have checked and ruled out so far tomorrow.

TylerSteez

iTrader: (3)

It could be the maf sensor, that's a quick easy repair

red rock

iTrader: (2)

Mechanics now day's don't have factory repair manuals for 30 year old cars, so my guess is they don't know anything about these cars unless the guy is at least 50 or 60 years old. But to find a mechanic that is sharp with TPI motors, your better off getting a manual and learning yourself. Or have a fellow member close to you help you out. Otherwise your just throwing money down the drain. The Dr. I bought my car from knew nothing about the mechanics of a car, so he kept taking it to mechanics that told him, " it's just old and that's the way it is". When I bought it, turned out to be a bad vacuum leak on the bottom inside runner causing a code 33. I wonder if they even know to disconnect the EST wire to set the timing.

Vinscully50

The other guy who is far away did replace my sending unit. About two years ago my car was acting like it was out of gas after only using six gallons. Two shops rejected my car as mentioned in my OP. A family friend recommend this guy and right away he said it was the sending unit.
He is in his late 50s/early 60s and did own a C4 Corvette back in the day. These guys are in there 30's and 40's. I was hoping they would be good since 5 people I knew recommended them but maybe they only know modern cars.

L0tuS

iTrader: (3)

If you double foot it can you get it to stay going while in gear or does it die? I would check and make shure the est was disconnect. Like red said when they did the timing another thing that will cause a car to just cut off once it goes into gear rare but happens is a bad torque converter

mdtoren

Im with these guys on everything above, vac leak sounds like best bet... Grab a can of car cleaner and start spraying. Theres so many gaskets on tpi motors compared to carb'd motors and its easy for one to fail, as well as lines all over if you still have emissions equip left to crack. Torque Converter would be worst case, and likely hardest to diag without it running...L0tus brings up a good point with that. If it ran fine before, Id doubt the min idle screw found a way to move itself..those things are pretty set in place.

Some suggestions - Check the IAC..could be clogged/dead enough to kill ya as the idle drops from park idle, also check your idle air ports on the TB, also could be clogged just enough.

As far as mechanics, good luck man. These days, all thats really left are "Computer techs" that can read a code and follow a decision tree...diagnosing issues is a lost and now, in most shops, a discouraged art. Working in the industry, we would much rather have someone just follow the diag tree because it works faster than a personal diagnosis, and its wrong less often. I went through a period of being frustrated that my car wasnt running, called a few places and was all but laughed off the phone when they found out it was OBD1..some charged double, even triple per hour with no real estimate as to how long it'd take compared to diag a non obd ii car..so I threw parts at it and bandaged my problem for an 1/8th of the likely cost.

EDGE

Grab propane, don't light it, and go around the hoses on the motor. If it goes up in idle, that's one leak. However I'd be looking at the torque converter. Maybe it's locked. I may be mistaken but that would be like quickly letting the clutch out on a manual at idle.

RBob

iTrader: (1)

Vinscully50, another item to check is the P/N input to the ECM. This allows the ECM to bump the IAC to prevent stalling when placed into gear. It will be an ORG/BLK wire at ECM pin B10.

When in park or neutral that line is grounded by the switch on the shifter. In any other gear that line will be at vehicle voltage (IGN+). Easy to check with key-on, engine-off.

RBob.

Vinscully50

Updates. Yesterday I had the car towed to the other shop far away. He's the shop that diagnosed and fixed my fuel sending unit issue when my car would die after half a tank.

He's owned a few C4 Corvettes so he knows what he's doing. I kind of regret not paying the more expensive tow and going to him first.

GCrites80s

Yeah you need a TPI guy. Also remember that shops get a lot of pressure from people whose dailies need to be fixed NOW. These people need to get to their jobs! It's understandable that a fun car sometimes needs to take a back seat to people's cars who come in smoking/steaming/not stopping/not turning/otherwise dangerous and can't take a day off work.

Vinscully50

UPdate:

The shop I took it too got it running, got it to where he can sort of drive it. But it acts like it has no power at first but then it does after forcing it. But it randomly stalls out after a little while.

This was fixed by replacing the cap on the distributor. He tried a MAF sensor to see if that would fix the lagging and stalling but no...

However, since I have owned the car when starting it up the check engine light has never come on. He noticed that too. Could a bad ECM be the cause of the random stalling?