fizzle

So I was driving along, about to pick up a friend to go out, and my CEL light came on, and the car jerked a bit. Now when I accelerate from a stop, its slow and sluggish. I plugged it in to a OBD2 reader, and got:
P0300 - random misfire
P0301 - cylinder 1 misfire
P0304 - cylinder 4 misfire

Anyway to fix this? Changed the plugs in November, so maybe a coil pack got loose? Guess I am going to have to go to the dealer for this one.

55fanatic

I would bet that you have a bad mass air sensor

fizzle

really? this would cause those codes? dealer wants $112 just to diagnose.

C43AMG

Pep Boys - CRC Mass Air Sensor Cleaner....about $7.00 a can !

fizzle

ok did that but couldnt get the MAF off, there looks like a 12 point star in there. what kind of tool do i need to get this off? i want to do a thorough cleaning.

C43AMG

Torx head , not sure the size

fizzle

nice. ill have to stop at Sears, dont have one that large. ill let you guys know how the cleaning goes. im at work now, so ill have to do it after work and the gym. see funny thing is last night, i reseated all the spark plug and coil pack wires, and it ran fine. now this morning starts up fine, runs for a bit start driving, get to a stop light and boom! i take off slowly and shaky, but eventually gets up to 30mph and is smooth. very odd.

C43AMG

BTW "fizzle"...nice stable !

fizzle

thanks, the rest are my parents cars. the ML is mine, but I get to drive the others on certain occasions. i have another question, if its not the MAF, what else would it be? coil packs? i remember seeing a link for MAF for like $200. does anyone have a good place to buy it online?

C43AMG

Be careful when buying any MAF's - if you have no choice other than to buy it - make sure it is from someone reputable.I have purchased items here :http://www.autohausaz.com/ and have been very happy with their pricing.You never mentioned it, but , how many miles on the vehicle?

fizzle

sorry its about 108k. changed the plugs at like 104 with iridiums. the car ran great, now i think the idler pulley and the MAF need to be replaced. while idling in Drive, its shaky. plus i get a bit of squeakyness.

C43AMG

Post your results after you clean the MAF.

55fanatic

I would bet its the sensor... My 55 has started shaking a bit at idle, Im thinking of Sea foaming it... to clean it

fizzle

hmm ive seafoamed it about 3 months ago, before replacing the plugs. now i got check engine light. cleaning the MAF did nothing. drove it around for about 20 min, still nothing. today i brought it into the dealer so we will see what the problem is. btw, i hear my model year has a harmonic balancer recall, as the dealer said it is but wasnt sure about my exact year. anyone have any recall info?

fizzle

ok just got back from the dealer. $625 for coil packs. had them replaced, as well as all codes reset. also, they fixed my intermittent gas gauge. also picked up a new gas cap, since the plastic strap broke. thanks for everyones help; appreciate it.

C43AMG

How's it run ?

fizzle

haha sorry about that. running great! even better than before the CEL light came on for some odd reason, guess it was about to go. Now just made an appointment for harmonic balancer since they couldnt do the work today. They didnt tell me if it was under recall tho, anyone know?

C43AMG

I thought it was for the 4.3 motors only, I could ( and probably am ) wrong.

fizzle

im trying to look for something on the recall, but am unable to find anything.

55fanatic

I thought it was 320s that had the recall

C43AMG

The reason I said the 4.3 is that I had mine done.