Car is dying on decel - around 3k rpm

[WagDatto]

I posted this in my build thread as well. I looked, but couldn't find an answer. Two nights ago, under deceleration, the 'Goon bogged down and died. Okay, no big deal, just a fluke? It happened a few times that night, I figured it was just the idle being adjusted a little wrong. Unfortunately, the next day (yesterday) it was the same story, as well as today...

With my car, I have the IACV blocked off, and I'm using the TPS (adjuster screw) to set my idle. I've had no issues before now. One thing I did find out is that the IACV came unplugged (shitty vacuum plug) and I thought that was the culprit. My thinking was that I was letting too much air in (through the TB and IACV) and it was causing me to run much too lean and die on decel toward idle. However, I sealed it using actual heater hose, and I still had the same issue.

1st, 2nd or 3rd gear, as soon as I decel to around 3k rpm (guesstimation, I don't have a tach) it starts to bog. Sometimes it will die, sometimes it will sputter and finally catch idle and be okay to go. KCNDizzle suggested MAF plug/wiring, as the MAF is the usual suspect for any problems around 3k rpm. I will check them tomorrow when it's light outside, and make sure everything is plugged in and secure, and there are no effed up wires.

Anybody have any other suggestions?

[ericcastro]

yeah,.....post some fricken video already!!!!

but naw, its sounds like its one of those simple gremlins that drive you nuts for about a week. And then you figure it out after spending $150 bucks replacing what you thought it was.

does it give you a flooded smell at all when it happens?? too much gas going in still and drowning the engine?? vacumm?? timing?? those are my guesses. MAF's are usually good or not. could try swapping a MAF with a friend and taking it out for a little test run??

good luck

[sumoboi7]

i hav no idea if u hav a sr or not but when i had my ka it was the coolant temp sensor that messed my shit up. it barely ran. the wires get old and dirty and need to be replaced with the plug after a while. if its an sr20 it sounds like the same shit i have now because i took off my recirculation hose so it tricks the maf to run rich after it blows off which causes it to bog and sometimes die out.

[HalveBlue]

My guess is MAF or vacuum.

[WagDatto]

Sorry, it's a KA. I figured the problem between the two would be the same anyway, so I didn't bother to clarify. Coolant temp sensor is brand new, wires are all connected. I will check all of my vacuum seals and wiring on the MAF tomorrow when I have some daylight.

As for smell, there's no smell of fuel. It doesn't seem like it would be flooding, because if I floor the pedal, it technically would even out the A/F mixture and give me major revs. If anything, it seems like it would be lack of fuel or too much air.

[mifesto]

is it KA or KA-T?

[WagDatto]

KA, as I said.

[los_inc]

make sure you blocked off your EGR not iacv or aac that needs air from the intake pipe before the throttle body
-los

[WagDatto]

Custom made plate blocking EGR. Usually the iacv needs air unless you use the tps adjuster screw to open the throttle body a crack, which works too.

[pbcstylez]

unplug the maf can u rev freely past 3k?

if u can than its not a maf issue

what u got sounds like your leaking air into the intake after the MAF. check ur piping from the maf to the throttle body

[WagDatto]

I'll try both those when I get home. I have no problems on accel, only decel. What does unplugging maf do for me? Excuse my KA newbiness! I have seen that suggested before, just want to know what it checks to rule out maf. I havnt checked for loose couplers yet so I'll do it in a bit.

Thanks for all the replies so far!

[leveloneae86]

ever got this fixed? im gonna try the maf method too.

[WagDatto]

Originally Posted by leveloneae86

ever got this fixed? im gonna try the maf method too.

Yeah, actually! I checked through everything and couldn't find ANYTHING wrong with the car. Finally, I opened my fuel cell and realized that I was out of gas. That would have been the first thing I checked had I not JUST filled the tank. After my first fuel leak, I made sure all my lines were tight and there wasn't any leaking. Gas prices are high, so I was bummed to waste the $50 tank on the ground and have to refill another $50. Needless to say, it got siphoned, and another $50 went into the tank. $150 in gas in less than a month, not including my other car, sucks. Investing $150 in a new old stock locking gas cap rocks! No problems since, gas gauge goes in next week.

Good luck with your problems!

[los_inc]

i'm glad to hear it all worked out
-los