1988 E30 M20 Stalls

[Mach5]

First post on this forum. Forgive me if I go too far. Some background. I don't actually own this car. It belongs to a widow. She and her husband are (were) long time friends, and he passed in 2020. I used to see him in this car and my memory of him is kind of tied to it. Which is a round about way of saying that this is a bit of labor of love.

I am a car guy and have worked on a lot of different models, but this is my first time working on an E30. This car sat for over 7 years. When I went to collect it, it was filthy, having sat outside unloved. It also had mold inside (convertible tops never seal perfectly). I got a ozone machine and killed and cleaned out the mold before taking it further. Since getting it, I have replaced the timing belt, water pump, t-stat and housing, hoses, radiator, fuel pump and filter, injectors, tires and likely other things I cannot remember. After a lot of work I was able to get it to start, and while bleeding the coolant it ran and idled fine. I didn't really drive it after that except in and out of the shop. A couple weeks later, I decided to take it around the block. It seemed to run fine at first. I took it fairly easy but did run it up to probably 3000 rpm. I only drove it around the neighborhood at speeds under 50mph. Total trip was less than a mile. While it ran great at first, when I stopped at a stop sign it died. Since then, it won't idle and I have to fuss to keep the engine up over 2500rpm just to keep it running at all.

It also is hard to start.

Right now I am dropping the tank. Going to have it cleaned and inspected. I got a new fuel filter on the off chance that it is sucking up crud from the tank and blocking the filter. Leaving that aside, are there any other things I need to consider as part of my hunt for a diagnosis and repair? Thanks.

[nadodude111]

Could be the ICV needs to be cleaned or replaced or the AFM has died. What year is the car? Do you get a check engine light?

[82eye]

First post on this forum. Forgive me if I go too far. Some background. I don't actually own this car. It belongs to a widow. She and her husband are (were) long time friends, and he passed in 2020. I used to see him in this car and my memory of him is kind of tied to it. Which is a round about way of saying that this is a bit of labor of love.

I am a car guy and have worked on a lot of different models, but this is my first time working on an E30. This car sat for over 7 years. When I went to collect it, it was filthy, having sat outside unloved. It also had mold inside (convertible tops never seal perfectly). I got a ozone machine and killed and cleaned out the mold before taking it further. Since getting it, I have replaced the timing belt, water pump, t-stat and housing, hoses, radiator, fuel pump and filter, injectors, tires and likely other things I cannot remember. After a lot of work I was able to get it to start, and while bleeding the coolant it ran and idled fine. I didn't really drive it after that except in and out of the shop. A couple weeks later, I decided to take it around the block. It seemed to run fine at first. I took it fairly easy but did run it up to probably 3000 rpm. I only drove it around the neighborhood at speeds under 50mph. Total trip was less than a mile. While it ran great at first, when I stopped at a stop sign it died. Since then, it won't idle and I have to fuss to keep the engine up over 2500rpm just to keep it running at all.

It also is hard to start.

Right now I am dropping the tank. Going to have it cleaned and inspected. I got a new fuel filter on the off chance that it is sucking up crud from the tank and blocking the filter. Leaving that aside, are there any other things I need to consider as part of my hunt for a diagnosis and repair? Thanks.

always do a search first on the board first. there really aren't many issues that you can't find a fix for already here. there aren't many members around to answer quickly any longer.

vaccum leaks are usually at the root of a lot of e30 running issues. if they aren't the culprit they will be adding to the base problem. smoke test is pretty much standard, start here with the engine management diagnostics. go to the top and bookmark the whole page as there is a lot of useful info.

[Mach5]

Could be the ICV needs to be cleaned or replaced or the AFM has died. What year is the car? Do you get a check engine light?

Thanks. We did test the ICV at one point, but it's worth looking at again. I did open the AFM and clean the contacts with a pencil eraser. Sometimes I don't remember everything I did until someone asks me about it, so it's a good refresher to get this kind of feedback.

It's a 1988. I put that in the title of the thread but I guess I could have been clearer or put it in the body as well.

[nadodude111]

Thanks. We did test the ICV at one point, but it's worth looking at again. I did open the AFM and clean the contacts with a pencil eraser. Sometimes I don't remember everything I did until someone asks me about it, so it's a good refresher to get this kind of feedback.

It's a 1988. I put that in the title of the thread but I guess I could have been clearer or put it in the body as well.

with it being a 1988, you have the ability to do the stomp test. If the ECU detected any faults, it will store the codes which the stomp test will reveal. It’s not very accurate but it can give you a clue as to what systems the fault might lie with. Here’s how to do the stomp test: https://www.racegerman.media/post/ho...e36-stomp-test

[Mach5]

Thanks. Diagnostics are on pause at the moment. I dropped the tank, and it had crud inside. It's being professionally dip-cleaned. Once I get that back together and I get new hoses and pump and sender, I can resume diagnostics.