Owner of 1986 245 that has been burdened by a intermittent stalling issue at stop signs/red lights and an erratic idle. Had multiple parts replaced/ cleaned - distributor , IACV cleaned , wire harness rewired & fuel relay replaced. Ran briefly (a few rides) w/o stalling . Now it is struggling to stay running right after starting and the tachometer is not reading accurately. All of the work was done by someone familiar with the car and resulting in multiple $$$. I am getting to the end of the road with repairing . What do you advise?Thank you

 

You did alot my friend...
Please start at the basics first
Then move to fuel filter, fuel pump pressure test etc

Look at ignition coil test and ignition module


Goldenblock
Senior Member

 

Thank you for responding. Please list what you consider the “basics “ for this problem

 

I noticed you mentioned cleaning your iac... Oftentimes this doesn't always solve problems if it is internally broken
Basics such as condition of sparkplugs, testing plug wires cap and rotor... These could all cause severe problems if original parts ..

Goldenblock
Senior member

 

These kinds of issues are very often caused by edgy MAFS (Mass Airflow Sensor). These sensors are tricky buggers and can act up in all kinds of mysterious ways. Maybe hard to find a good one anymore, but don't settle for a cheap Chinese one, you'll never know if it did the trick. Best way is to swap for a "known good" one to diagnose correctly.

 

Hey @lev :
Very glad to see you're still on here.
After lifting my 1990 (Regina) 740 out of a two-year no-start condition (finally tracked down the culprit, a fuel pump malfunction, fix as simple as tightening a tiny hose clamp), my idle is uncharacteristically horrible (moving between steady and bouncing, though it seems fairly normal/constant RPM-wise; the ECU is throwing a code of 2-2-1. Not the "O2 sensor signal missing" code but the "O2 sensor not operating" code (I don't know what that means; is the sensor gunked up?). Or it could be an "intake air leak," according to the code table (which leak I'm given to understand would be somewhere downstream from the MAFS, the stream flowing from air filter to intake manifold). I've cleared codes, tried "burning out the gunk," code keeps reappearing and idle still ****ty.
What does "sensor not operating" mean, what is the best way to test which of these two possible conditions is causing the code, and how best to remedy?
Sorry to still be so basic here. Thank you very much for all your help in the past!
PS. I don't know if this needs to be added here, but the FPR is new.

UPDATE (in case I'm not persona non grata by now): 2-2-1 shows up when car reaches operating temp (after having cleared codes by disconnecting battery). Also seems to be tripped by car choking momentarily on a big upchuck of condensation (lots of water still dripping & spraying out of tailpipe, lots of mayonnaise on the inside of the oil cap). Took a voltage reading, voltage moving between 1.2 and 1.4 volts (after operating temp is reached/code shows up).

FINAL UPDATE: Looks like the code was being tripped by a super-rich mixture that was caused not by an air problem but by a fuel problem, namely too much fuel. Before I ended up going all the way back to the fuel pump I had replaced the old "yellow top" injectors thinking that maybe they were fouled and that's why my plugs were dry and odorless (got replacement "yellow tops" from partsgeek.com cheap rather than troubling with cleaning the old ones). I noticed when I put the new ones in that they each had four nozzles instead of one like the originals but at the time I thought the more the merrier, I need gas on the plugs dammit. I now think that it wasn't just water getting spit out the tailpipe but uncombusted fuel?? Anyway, old "dirty" plugs back in and she's back to purring like a kitten, with not a code in sight. Thanks for being there (even if only as a sounding board)!

 

I have had intermittent problems with my MAFS on my 93 240 wagon. I believe I replaced it ten or more years ago. But I have had stalling problems similar to the original poster since then on at least two occasions. The engine codes tell me it is some combination of MAFS and O2 sensors. It seems that unhooking things and hooking them back up can sometimes fix the problems, when it is related to the MAFS operation.