i had a nitrous backfire threw the intake a while back without any major damage besides needing a new filter. long story short, the problem was routed back to me for not purging before i sprayed at such a high shot.

everything was fine untill recently. the engine has developed a very rough idle. even a clunking at times. i was wondering if that had anything to do with my MAF sensor going bad. i havent used nitrous since the backfire either.

what are the effects of the MAF sensor going bad? what am i looking at cost wise to buy a new one?

thanks.

 

Do you hear the clunking consistently? Is it only at idle or do you hear it and it gets worse as the rpm's get higher? Just a guess, maybe you damaged something internally? I have no clue what the effects would be of the MAF sensor going bad. I may be totally off, so someone else chime in.

 

Usually if the MAF is going bad you get improper airflow measurements to the ecu. Usually results in a low idle and or stalling.....but not clunking

 

That's what I thought about the clunking, maybe he bent a rod?

 

I would get a compression test done ASAP. That would reveal any ring or valve issues in the heads. Try to narrow it down before spending a ton of cash.

 

Yeah, I havent heard of clunking from a bad MAF sensor. If they go bad, you will typically get a badly idling and running car, and a CEL. They are expensive....around $300.

I had a weird clunking type noise on my car, and I traced it down to an exhuast manifold leak. At idle, the air would back up in there, and occasionally clunk from time to time.

 

ouch. i hope its nothing as serious as messed up internals.

the clunking only happens on warm starts and only when the car is at idle. its fine once its in gear and smooth as butter at high rpms.

i have a wb air/fuel gauge installed. whenever i hear the clunk the reading stays within specs but does a quick spike towards the lean end of the spectrum. i dunno it that accounts for anything.

where can i get a compression test done?

i appreciate all the input im getting.

 

You can get a compression tester with a gauge from pretty much any car parts store. I know Autozone carries them and I am sure the others do as well.

To do a compression check, you need to take all your spark plugs out, screw the compression sensor in each spark plug hole (one at a time) and crank the motor until you get the highest reading on the guage. Usually 2 cranks per cylinder does it. Make sure to mark down each reading from each cylinder to compare them to each other.

If you need additional help on this, PM me. Good luck.

 

Did this happen with the stock manifolds or the Greddy?

 

I've had a MAF go bad (not on my Z). If I started the car cold and then pressed the gas pedal, the engine would stumble and shudder.

My guess is that your "clunking" is just running too rich.
--
Jeff

 

excellent. ill swint by and pick one up tomorrow. i've been wanting to go back to my stock pulgs anyway, so this is more incentive to do it.

i guess its not the MAF then. one less possible thing.

 

i just got the parts for a compression test.

im guessing since 5 of the six spark plug holes will be uncovered while im doing the test, wont that mean ill get a nice shot of gas coming out from them every time i turn the key to crank the engine?

does anyone know what pressure readings are considered within compression specs?

thanks for the help.