sTenGuy69

Car's been running great until now. Here's some background: doing some spring cleaning I cleaned the MAF "barn door". To help trace down an oil leak, I very carefully cleaned the crankcase with hot water and simple green to help see where it was coming from. Before finishing up, I noticed a leaky coolant line and a broken vacuum line going to the TB. Fixed both and fired it up for a test ride.

Started with no issue, so I went on down the street. When I hit the throttle it started stumbling and nearly died like its waay lean. So badly I couldn't even make it up the hill back to my house.

Weird thing is, it seems to be ok if I give it a lot of gas and was finally able to get back into the garage by nailing the gas. So what could I have damaged? Maybe I bumped the a/f screw when cleaning the MAF? God this sucks...

Maleficio

Is your AFM connector securely inserted into the jack? Sounds just like what happened to me yesterday.

My plugs (Pulstar) went bad after using Amsoil Powerfoam in the intake. So I replaced them with OEM-style AC Delco. Car still ran all screwed up. I finally realized that I had forgotten to reinstall the AFM connector. Car runs great now.

Oh yeah, I was barely able to make it back home, too.

VehiGAZ

Only runs with lots of pedal = rich, not lean.

Sounds like it could be MAF-related, but could also be a fried LH, as the symptoms you describe sound very similar to my recent LH failure. Suggest to R&R the MAF to see if it helps at all. You should also be concerned about the water or leaks shorting a connector, of course.

Lastly, depending on your MY (you really need to post that info if you're going to get any helpful responses) you could be in ignition-protection mode for one reason or another, which is easy to determine (red or green LED lighting up on Ignition Monitoring circuit relay next to EZK controller on MY '89 and up).

Good luck!

AO

If it's a "Barn Door" then it's not a MAF. What year?

Mongo

If it is L-Jetronic, what did you clean AFM with?

sTenGuy69

Sorry, forgot to post the MY. Its a 79 US automatic. Incorrect terminology using MAF (my bad). The "barn door" was gunked with oil so I just wiped it off (no cleaner). I'll bet the problem is in that area, but I won't be able to check for a couple days now :-(

Mongo

Isn't the '79 a CIS car? I don't think there is a barn door but a throttle plate. However, if you cleaned it, you may have misaligned it somehow. These things have a specific clearance if I remember correctly reading in my Bosch injection book.

sTenGuy69

Yes it is. I'll avoid using slang to describe parts. The Bosch K Jet manual refers to the plate that I cleaned on the mixture control unit as the air-flow sensor. I'll make sure thats set to spec and aligned.

Mongo

Happened to my Dad on an '84 190E before. Let us know if you need any other help.

VehiGAZ

I bet I can think of a couple of other things that happened to your dad's '84 190E... was there perhaps an air conditioning compressor replacement (or two? or three?).

Mongo

We only went through one. We sold it 5 years later after we bought it to buy another house. We loved that car to death.

VehiGAZ

I loved mine, too! It was a euro-market olive-green color that I only saw one other time outside Chicago. My mother got a '92 (IIRC) after I sold mine - she put 100k on it before trading it in a few years ago and it looked brand new when she did.

sTenGuy69

Finally got time to work on it... Was able to get the mixture "ok" for now, but it seems like it runs decently until it warms up or goes above idle. As it warms, the RPM's get progressively lower until it dies. If I give it any gas, it stumbles (unless I really hit the gas). Ideas/suggestions?

porsche 928 RI

check and see if the t-belt jumped, mine had the same strange stumbleing issue

sTenGuy69

Yikes... Did your's idle decently also?