I am stumped, i have an 86 240 dl, the car was running great, then it acted as if it wasn't getting enough fuel, it will idle, but when you try to rev it up it only goes about 2000 rpms then cuts out, if you keep your foot in the gas it will shut off, if you let off it will go back to idle and stay running, if you put it in gear it dies, i have replaced both fuel pumps in line and in tank, i even had to replace the sender unit in the tank cause it was not sending juice to the rear pump to work, break in the pass thru wires, it has 30 lbs of fuel pressure, i also replaced the fuel filter, i have no i dea what to do please, if you have seen this before give me a hint, i am clueless thank you..............

 

Please search before posting this has been talked about many times.

But look at Mass flow sensor,engine speed sensor/Dist pickup,Power stage,

 

Sorry Tech, but that's how it goes sometimes, i did search , but i did not come up with any posts with this type of problem, maybe you could help me find them, your help is appreciated. You mentioned the mass air flow , i did try to clean it and made sure all of the connections are tight, but how can i test it, i really hate to keep throwing parts at this car, i am a competent mechanic, i just have very little info on this car and how to diagnose it. What and where is the engine speed sensor, and how do i test it? Powerstage, what and where is that??? I'll check the pickup too, but most cars if the pickup is bad they just won't run, right??? Thanks again for any help you can give me....

 

Also one more quiestion has anything else been done to the car?

If the car has a Dist. pickup then it won't have the speed sensor.

Power stage if it has one will be on the drivers side inner fender.A sensor mounted on an Aliminum plate.

Also it could be a bad coil have been seeing alot of that lately with the same complaint.

 

No, there was nothing done to the car prior to this happening if that is what you are asking. It was running fine and it is bone stock, i did get some gas shortly before this occured so the first thing i thought was bad gas, i did not flush the tank, but i did get some gas from a different place and put in the tank with the other gas, then i changed the fuel filter, did not help, so i changed the main pump, did not help, i tested the rear pump and it was not working, so i replaced it as well and retested it, it is now working and i still have the same problem. I found the fuel pump relay and visibly inspected it for what that is worth but did not replace it because both pumps are working and the fuel pressure is within spec. It does have a distributor, i will look tommorrow for the power stage, but what does the power stage do? I will also try to test the coil to see if i lose spark when the car dies, but what i don't understand is that most of the time when a coil is bad,the car just won't run or will run very poorly at best, this thing purrs like a kitten at idle and off idle up to a certain rpm then just dies if you keep your foot on the gas, no spit, no sputter, just dies, then if you release the peddle before it shuts completely off it will return to idle and run like normal. Hope this description helps a bit more, i will try what you say, but is there a way to verify or test any of these parts being defective prior to replacing them, i mean i know i can ohm the coil, which i will try tomorrow, i will also put my timing light on a plug wire and have someone hit the gas to see if i lose spark when the car cuts out, and i should be able to test the pickup coil with my multimeter, but what about the mass air flo and this powerstage, if you could tell me what it does i may be able to test it also, SORRY FOR THE LONG POST and for being a P.I.T.A. , thanks again......

 

http://www.brickboard.com/FAQ/700-90...ceSymptoms.htm

 

Try unplugging the mass flow and see if the car runs better. If it does somewhat then it is bad.

I have seen the coils do exactly what your car is doing when they go bad as well.