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sethlamb
10-30-2010, 07:08 PM
So i had the car cbecked out today. The mechanic said the car was fine. The car keeps thriwing a check engine light and then idles like its running on less than 6 cylinders. Then it corrects itself and runs fine. Cel stilk stays lit. Any ideas.2.8 quattro

Insomniac
10-30-2010, 07:13 PM
What code is it throwing? That's number one.

coolgraymemo
10-30-2010, 11:20 PM
yea, we need codes...

walky_talky20
10-31-2010, 12:14 AM
Did he check the plugs and wires? Also could be oil in the plug holes. Having the codes will really help narrow it down, though.

stack
10-31-2010, 12:10 PM
running on less the 6 cyl
is p0300(something with a 300 in it) random misfire multiple misfire
coil packs perhaps

sethlamb
10-31-2010, 02:25 PM
Yes. Its throwing a 300 code. Cyl misfire. I dunno what to do

walky_talky20
10-31-2010, 03:19 PM
I am going to suggest you take the car to your mechanic and tell him you have a check engine and what seems like a misfire problem. He will diagnose and fix your car and charge you cash dollars for it.

If you really want to tackle this yourself, your first step is to see if it just 1 cylinder misfiring, and which one it is. Vag com would be helpful to just watch the misfires happen. Or if it is just 1 bank, or all cylinders. Inspect the plugs and wires for spark tracks up the insulation and porcelain. Check the strength of the spark on each cylinder. You can also make sure your MAF is working good by logging it and checking your fuel trims to make they aren't out of whack. If everything checks out, then you might move on to a compression test. After that, perhaps swapping injectors around, but I really don't think you'll get that far. It is probably just a bad plug wire or spark plug.

sethlamb
10-31-2010, 04:20 PM
The scan tool said multiple cylinder misfires. Does the 2.8 have individual coils?

wildbill
10-31-2010, 04:41 PM
The scan tool said multiple cylinder misfires. Does the 2.8 have individual coils?
fail

sethlamb
10-31-2010, 06:23 PM
any ideas....not really sure what "fail" means

protocol_droid
11-01-2010, 07:41 AM
any ideas....not really sure what "fail" means

He means you should already know the answer to that one and you "fail" because you ask the question.

Do as walky talky suggests above. If you have a vag, run the logs to check your maf first. If that's okay, more than likely your symptoms point to a faulty coil plug/plug wire/spark plug. Git r dun.

sethlamb
11-01-2010, 09:09 AM
Thanks. Sorry if i ask a ammeterish question. I have onky had the car for a week and havent dove into the motor yet.

walky_talky20
11-01-2010, 09:32 AM
No, the coils are not separate. It is 1 unit.

If you plan on keeping the car and doing some work yourself, you should really buy a vag-com cable. They are $15 shipped on ebay and the software is free. Then you just need a laptop (or borrow one) and you're set for doing some pretty good diagnostics.

chris164935
11-01-2010, 09:40 AM
Honestly, if my car was throwing a CEL and my mechanic said my car was fine, I would seriously consider a new mechanic. Now, maybe misfiring isn't that big of a deal, but you won't pass emissions with a CEL. You'll also get crappy gas mileage. Not to mention how bad it could get.

sethlamb
11-01-2010, 03:19 PM
So the issue is this. Im getting cylinder misfires on 3 of the 6 cylinders. The mechanic recomended a change in plugs and wires and a fuel system cleaning. I also have a slightly bumpy idle. I thought was a warn motor mount but the mechanic thinks it could be a clogged fuel injector. Should i do a fuel system cleaning first before replacing plugs and wires?

coolgraymemo
11-01-2010, 03:34 PM
Yes.

You should also sea-foam.

sethlamb
11-01-2010, 05:06 PM
I bought the sea foam. Hope it helps. The car almost brokedown in tbe way to pepboys to buy the stuff. Im so annoyed.

adema69
11-01-2010, 05:23 PM
VAg com

sethlamb
11-02-2010, 05:41 AM
So after getting the codes read again last nite. 3 of 6 cylinders are misfiring. Im sick of messin with this. I can get bosch plugs, wires, and a new coil for 215 bucks. Should i just replace the stuff and hope it works? The mechanic is gonna charge me 90 bucks an hiur to diagnose. I an change those thins in my garage for free. Will i need anything special to swap the coil pack. Is t easy to get to under the hood? What gap should i run on the plugs?

protocol_droid
11-02-2010, 08:43 AM
So after getting the codes read again last nite. 3 of 6 cylinders are misfiring. Im sick of messin with this. I can get bosch plugs, wires, and a new coil for 215 bucks. Should i just replace the stuff and hope it works? The mechanic is gonna charge me 90 bucks an hiur to diagnose. I an change those thins in my garage for free. Will i need anything special to swap the coil pack. Is t easy to get to under the hood? What gap should i run on the plugs?

if there's one thing you can learn quickly, it's to put in your own spark plugs/coil packs. It takes but 15 minutes even if you're slow. Don't pay anyone just yet.

get a set of new new spark plugs and gap them correctly (don't trust pre gapped plugs) and change them first. Check for codes at this point. If you still get the same codes, then swap cylinder #3 or #6 coil pack to one of the other cylinders (1,2,4 or 5)and then recheck the codes to see if the errors have now changed cylinders. If they did, you've just found your bad coil pack. Git r dun.