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My 92 mx3 gs this morning started perfectly fine and sounded normal, I drove to the store and when I restarted the car, it "gurgles" sound from the muffler and especially when taking off. This thing hesitates to get up to speed also but has moments where it acts fine (no gurgling) but only lasts a few seconds. Where do I start? Fuel filter? Spark plugs are good and there is spark to each wire.

Vac hoses are a good start, could be an EGR valve as well. Suggest your try SeaFoaming your engine. If it smoothins it out for a short time could be the EGR is dirty.

yea i agree vac lines and as well

I'm going to disagree with Dan. Don't start with seafoam.

K.I.S.S. First just look at your intake. The intake hose may have cracked or a connection could have spread open. The VAF harness plug may have popped off. Move things in the intake around gently with your hands and see if anything obvious seems wrong. Look at the little plastic tees that connect the vacuum hoses. It would be weird for a hose to come off but not so weird for a plastic tee to snap.

It would be EXTREMELY unusual for your EGR valve to suddenly affect yoru idle that dramatically while you were in the store. In fact I'm going to say nearly impossible.

Well I've had vac issues prior to this and the car idle surged and that was it. I've replaced the vac lines to the best of my ability and have a custom cold air intake on the car that I moved the other day (taped it forward cause the MAF sensor plug kept jiggling out and disconnecting which kills the car automatically). I currently moved it back and looked all around the intake and nothing looks bad or anything.


My K&N filter is a bit beat up (ran it over cause it fell off the attachment) but I put it back on and also there is a leak of coolant next to the filter, but I doubt it'd cause this type of issue and the MAF doesn't have any coolant in it or look wet but the filter kinda had some on it/in it.

I'm at a loss of where to begin with the issue because it just happened so sporadically because it was like once I restarted the car it started doing this crap. I'm going to attempt to test fuel pressure but not sure my gauge will fit the thing on my car.

Based purely on your description of the intake...parts of which you have recently run over!!!...I would wager a testicle that it has nothing to do with fuel pressure.

I vote timing issue. The motor sounds funny if your timing jumps a tooth.

OK I don't mean to be a jerk here...I really don't. but I want to explore this because this is something that a lot of people do who don't have a lot of experience troublshooting stuff.

"My car runs badly all of a sudden."

"Check the intake and the VAF."

"I just worked on the intake because it was LOOSE and the PLUG TO THE VAF KEPT WIGGLING OUT...must be a fuel problem."

If you have a history of issues with the intake, and the VAF has come unplugged more than once, this is almost certainly the origin of your problem. Don't start chasing new stuff until you are sure that the stuff you know has been a problem in the past...i.e...been run over...are absolutely solved.

The coolant leak is also possibly significant.

The reason I skipped to fuel pressure is because I've explored my options at the intake and Maf sensor and nothing seems to affect the issue. The Maf is plugged in and working and the intake shows no sign off leaks or issues.

Well maybe I'm wrong.

Next step then is to ask yourself what would cause the engine to sputter like you describe. I don't think fuel would.

Timing is a possibility but it's pretty unlikely that the timing skipped while you were in that store. To confirm the timing put the crank pully on the TDC mark. If you remove the no.1 plug and put your finger over the hole as someone turns the engine you can feel compression come out. If you don't feel compression turn the crank one more full revolution and align the mark again. Now you should feel compression. Remove the distributor cap. The rotor should be pointing roughly at the no.1 contact. Or you can remove the top timing belt cover and check that the cam sprockets are aligned with their timing marks, but the distributor rotor should tell you close enough.

Air is the most obvious cause of what your describing. And given that you have had issues with the connection to the VAF and pieces falling off that's where I think you will find the problem. Make sure there are no broken wires on the VAF. Make sure the breather hose didn't come off your intake tube. It sounds to me like the ECU can't figure out how much air is getting in, either because there's a big leak or because the signal from the VAF is gone or inaccurate. My engine runs with the VAF unplugged...but horribly.

I vote vaf/air intake. Tricky little beeps that are a pain to diag. Be sure everything is secure and your VAF cant be moved at all in the intake, otherwise your getting air past it and its a problem. Also double and triple check all your vacuum lines this will have a big impact and the diagrams are easily available, just search my trouble posts lol

Well...turned out it was a faulty spark plug wire (found out it was sparking out the side of the wire instead of on top the plug).

I admit that suprises me. I have had all three of my front plug wires leaking and still ran pretty good. In the dark it looked like a Led Zepplin show under my hood.

Gald you figured it out. Sorry if I gave you a hard time.

Wytbishop, the K.I.S.S advice you gave was correct.

Plug/wire faults are staying true to the motto of keep it simple, stupid