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I purchased this vehicle a few months ago and I'd like to start fixing it up some.
It has a significant valve cover leak which is no biggie but I also have a list of error codes too.
Is there a good test I can perform for the MAF sensor to confirm it is indeed faulty? (I'm handy with a DMM)
I've chased a MAF issue in the past on another vehicle and the sensor wasn't the problem.
The transmission works 95% of the time but likely needs a valvebody job based on what I've read.
I also have a Cylinder 8 misfire and a random misfire code so I'll start with checking the plugs.
This is the 1st MB I've owned but I'm very comfortable working on cars.
The car has 172k miles and runs great other than an idle throttle surge and the transmission going into limp mode randomly. (again, I know how to fix the transmission issue)
I had the same issue with my transmission recently. Thankfully it was just the electronic connector ($18) was leaking and fluid was leeching itself through there and shorting connections. It had wicked trans fluid all the way up the cable into the TCU in the interior (passenger side footwell, 15 minutes to access).
I cleaned the TCU with electronic parts cleaner, replaced the connector plug and hosed the area down with brake cleaner. Limp mode went away, as did the P code.
Sounds like yours also has a clear cut case of bad MAF. Sadly, the affordable options are a crapshoot; you might get lucky or you might need another one in 6 months. The OEM Bosch units are a sure thing but they are pricey, at $400+
Cool, I'll try the connector replacement 1st before I go all out on the conductor plate.
Are there any known issues with intake manifold gaskets, ignition coils or injectors I should be on the lookout for when trying to remedy the misfire?
I'm going to start with the MAF sensor along with plugs in hopes that will take care of the misfire codes.
Since you have a misfire and MAF, I'd start with cleaning/replacing the MAF.
If it's just the misfire codes, from my experience, replacing the corresponding coilpack did the trick. One time it was also bad/stale gas causing a misfire.
Good points, if the misfire codes are always for the same cylinder, focus on the plug wire, then the plug, then the coil, and then the injector. On mine, I had a bad coil once. On my friend's, he had a bad injector.
But if the misfires are random, almost always points to a MAF. That, or a vacuum leak.
Thanks everyone. I ordered the MAF to start along with the new transmission connector.
I'll get those swapped out, reset the codes and I'll follow-up afterwards.
You can also swap the coil from the cylinder that shows the miss fire to another cylinder and see if the misfire goes to that cylinder. If it does then you know you need a coil. Same with spark plugs and wires. It’s always best if you have the cash to just buy everything new.
Best thing with everything new is that it will last you many years to come.
Couldn't agree more. As a long time C43 owner, it's getting hard to adjust to these new owners now that the cars are finally starting to be bought by people who appreciate them as classics. For so many years we just answered questions here from people who were just looking for the cheapest, fastest solution.
But this is a 20 year old, very rare and special car. The best decision here is to replace those ancient wires, plugs, coils, and valve cover gaskets in one big job.
Well, I'm still waiting on the valve cover gaskets to arrive, but I went ahead and did the MAF just to see what would happen.
The sensor definitely was due for a replacement or cleaning. It has some sort of rust type corrosion on it, sort of odd.
After replacing that and pulling the battery for 10 minutes she's running so much better.
The idle surge is gone and wow what a difference in performance compared to when I 1st drove it.
All the CELs are clear even after a 50-mile drive.
When the valve cover arrives, I'll snap some pictures of before + after.
Some pics of mine. Sparkplugs werent horrible but the car sat a while so figured id change them as well as the wires. Coilpacks were cleaned and valve covers were hot tanked.
Some pics of mine. Sparkplugs werent horrible but the car sat a while so figured id change them as well as the wires. Coilpacks were cleaned and valve covers were hot tanked.
Heck yeah, those plugs look really great on the electrodes!
ooof, I just noticed the valve cover leavings.
How difficult is it to get the stock remnants off of these heads?
I deal mostly with SBC engines and they typically come right off (mostly because they're 30 years old and soaked with oil) but those look pretty dry considering.
For anyone looking at this thread I wanted to post a picture showing the windshield wiper fluid tank removed. Removing it is not hard and when removed there is much more room to remove the plugs and wires on the driver side.
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