Surge

Misanthropy

Misanthropy

Information Junkie
I am troubleshooting a surge I thought was first at only a certain acceleration, but it is now upon me at idle somewhat. My question is: does a dirty or failed MAFS kick check engine on obd1?
 
With the OBD 1 it's a hit and miss. Some EEC calibrations have a wider threshold before setting off a CEL so sometimes the failing part never sets off the CEL.

Also, check for an ignition miss, bad wires, fouled plugs and of course the IAC valve sticking which is a real PITA to even see let alone remove and inspect or replace.
 
My first gen would only toss a CEL for stupid stuff like a EGR valve, but would not tell me my maf was bad, or my fuel pump was bad...etc.
 
Yeah I am going towards MAF even though I cleaned it a couple months ago. Replaced TPS,IAC, EGR valve, wires,plugs, valve cover and stem seals (which ya the spark plug used to have oil on it), coil packs, vacuum regulator, DPFE, etc.

At first I figured TPS or IAC which i just did a couple days ago, because the surge was during slight acceleration, but then in neutral it started acting up which leads me to ignition or MAF. I do have the K&N panel filter so maybe that gummed it up or MAF just failed. Luckily I have another M8 10 feet away I can swap parts from :p
 
I forgot to ask, do failed oxygen sensors have these type of characteristics? 165k on car and I don't believe they have been replaced before I bought it at 129k.

Oh and Lonnie I love the tranny :p
 
You said you just cleaned the MAF a couple of months ago.....do you have in one of those "wet" type air filters? If so, the MAF could well be dirty again! Spray it with cleaner again and if it clears up, get rid of that thing and re-install the stock filter system! Everyone seems to OVER-OIL that aftermarket filter!
 
budpytko said:
You said you just cleaned the MAF a couple of months ago.....do you have in one of those "wet" type air filters? If so, the MAF could well be dirty again! Spray it with cleaner again and if it clears up, get rid of that thing and re-install the stock filter system! Everyone seems to OVER-OIL that aftermarket filter!
Click to expand...

Yeah, I switched back to dry also.

I went with a Wix brand filter.
 
I swapped the MAFS from the other m8. At first I felt it, but then it went away for the most part. I might have felt it once within a 30 minute driving period.

I will clean the MAFS and replace the oxygen sensors. Just in case the spark plugs will be pulled tomorrow.

Thanks for the advice fellas.
 
I had a miss/studder in the engine today. I have an Innova Model 3130 scan tool which I hooked up to the car (I didn't get a CEL) and it didn't show any codes, so I left it hooked up and took it for a ride. Beautiful, went a round the block and got back into the driveway and the scan tool said "Misfire Clylinder # 7". I had a spare coil-on-plug and boot. Installed it...another ride...all is okay again. As the old boot looked good, I assume it was the coil. I recmmend the 3130 to you all. If I wanted to spend more on it, the company has an upgrade to include scaning the ABS system too... I declined...It was more than what I paid for the scanner on ebay.
 
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