1991 300GT SL stalls when driving

Then those were not the problem. Keep the parts as spares. It sounds like an electrical problem thats surfaced when the everything was moved around during the engine replacement.

When the engine stalls, does the Check Engine light come on? Any other electrical symptoms? I'd R/R all the engine connectors, giving them each a squirt of wd40. Find your ECU (center console or RH pillar), and take it out. Open the can and look at the electrolyic capacitors. Any of these leaking? Is there a fishy smell?

Stewart DIBBS

Yes the Check Engine light comes on when happens. Of course if I am driving

looks to me that you are in the right direction about something electric is going on. I will check what you suggested and see from there. Thanks. I will post what I find for reference to others as well.

What is the code it throws? That will save some time. You can borrow a "1G logger" from any 3K or DSM group in your area. My logger works with DSMs and

3Ks, so I know it's doable. Where are you and someone (or I can point you to) will be able to help.

I haven't put it to a logger yet. I am taking it to my mechanic tomorrow and we'll try your suggestions here. I am in central Texas, USA. The mechanic insists that he have seen fuel pumps failing even when they are new, so we have a few things to check on. Thanks a lot to all of you guys. FSG.

Not impossible, but very unlikley, as a fuel pump that stops working results in the engine slowing down and then stopping as the fuel pressure drops off, not just cutting out instantly.

Stewart DIBBS

try driving it with the gas cap off, could be a pinched vent line or the evaporative emissions canister is full of fuel...you don't always try to squeeze in more gas after the pump shuts off do you? TG

I'm betting a CAM angle sensor failure or ECU caps. I can't remember if the TDC code is stored or not. You may have to have the logger connected when it happens.

I can't wait for the weekend to test all the interesting things that you guys have posted here, something that I noticied and maybe it have nothing to do with it but anyways is that when that happened I was using the air conditioning and as a rule I always turn it off before shutting the engine off, but in a couple of cases I shutted the engine with the AC running (the car have a digital ac, not the dials) and the turned the engine on with the AC on. Well I have been driving short trips without AC and nothing have happened so far .... so I was just wondering if that sounds like a clue to somebody. I will drive with the gas cap off and see and some of the other suggestions as well, by the way where can I get a 1G logger in my area, central Texas USA. Any ideas? Thanks again.

When the AC is on, the ISC is stepped up to allow for a higher idle. I've never owned an auto, so I don't know if that is valid with them. If so, you could add a bad ISC as another possible problem.