Hey guys,

I've had this car for about 6 months now. Its an '83 244 dl with an auto trans. Everything was going great until it started to get cold out (the temperature may very well be a coincidence).

Whats going on is the car will randomly stall on me, only ever at idle. It doesnt matter if I've been driving for 30 seconds or an hour, and will sometimes do it once a day or 5 times in an hour. It has never struggled to restart after stalling, but has had a few morning where it didnt want to start first try. It will occasionally cut power on me for a split second while driving, and then go back to normal right away. It also will occasionally not give me any power when pulling away from a stop. When it does this, it will usually go back to normal within 10 seconds. It did this this morning, but actually was giving me less power when i pressed the pedal harder, and slightly more power when I was very gently applying throttle. This is the first time I've noticed that.

So far I have replaced (just as general new old car tuneup stuff, and a few attempts at fixing this issue) plugs, wires, distributor, all new belts including timing, flame trap, fuel pump relay, both fuel pumps and filters, cleaned the throttle body, repaired one vacuum leak and have looked for others.

I had high hopes for in-tank pump being the problem, because the car was incredibly lazy and surgey until the rpms would get up to 2500-3000 (guessing, I dont have a tach), and then it would noticeably free up and feel much quicker. The new pump has pretty much eliminated that laziness, but the stalling and power cuts are still happening.

It seems like most threads I've come across mention difficulty starting back up after a stall. It always starts right back up like nothing happened.

I'm assuming its electrical at this point, but that is unfortunately my weak point when it comes to repairs. The fact that it starts right back up is making me think its not fuse related.

Any help or insight would be much appreciated.

John

 

That's sounds like a really strange problem. You said you checked the fuel filters and relay, but have you checked the injectors? Maybe one or more is leaking a whole lot and flooding a cylinder. Have you checked to see if you've got any error codes? Not sure if the 83's had it, I've only owned 90+ models...

 

OBD1 diagnostics were new in 1989, with LH 2.4

an 83 is probably LH II, which pretty much was the first version.

 

You have done a bunch but one I had was the check valve just before the under the car fuel pump. Easy check is to pinch off the fuel return line and see if that helps

The other weird one was the feed hose splitting that was feeding the in-tank pump.

 

is the idle on this car otherwise solid? once warmed up, it should idle about 600-700 rpm, and putting it in gear vs neutral should make only a blip then it should settle right back down at the same RPM.

TnBob's advise would cause the fuel pressure to be way too high, I would NOT recommend that. in fact, that could burst the fuel pressure regulator membrane. a bad fuel check valve will make the car a little harder to start, but should have no effect when tis running and hte pumps are on.

I had somewhat similar problems on a Mercedes that had CIS-E fuel injection (aka Ke-Jet), that turned out to be caused by dried out injector seals, letting too much air in around the injectors, car drove OK but would sporadically stumble and stall at idle, or when you tried to give it gas to accelerate from a stop. was really frustrating because every time we did something to the engine, it would run fine for a week, then start stumbling again. new injector seals (and new injectors because 3 of the 6 failed a pop test) and voila, ran like a new engine again.

 

My advice is based on an actual check valve failure and doing as indicated to locate the failure. I am certainly not recommending the 240 be driven like that !