engine shuts down

[nismo7]

This is the second time I have experienced this. Each time it occured after high speed acceleration on the interstate 5th gear 80+ mph, 1/4 tank of gas and high rev down shifting getting on an off/on ramp. Same place. The engine is running great and as I down shift to 3rd going into the turn, the engine stumbles and I loose power when I step on the gas. The engine shuts down. When I restart the idle is very erradic up down / up down etc... This last time it happend I got out and removed the fuel cap and I got a lot of air. (Vacum lock??) What would cause this and how do I fix it? Thanks ahead of time for anyone who can help me.

[Scott McLellan]

Air being sucked in when you unsrew the fuel cap is normal. Does the check engine light come on or anything?

[nismo7]

no nothing, it's like it's running out of fuel. No lights just total loss of power.

[Touchdown038]

Something fuel... I wanna say pump but I'm not sure.

[allens 240sx]

same problem here, i was told bad gas, but i've add treatment and ect, try running the old out and putting new in, still screwed...

[MrFox]

Do you remember what speed/RPM you were at when downshifting into 3rd?

[nismo7]

I was coming off the interstate, had gone to fourth to slow before the apex and went to third to accelerate at around 45mph 4k rpm. Nothing odd I do it every day, it has happened twice. When I hit the gas, it boggs down like it's miss firing and the more gas...the worse it gets.. and then I shut it down, restart and the idle goes 750 down to 300, back up to 750 down to 250 up down up down etc.. I got out released the fuel cap and it started up again and I was back to normal. Ran fine. It's just a dangerous situation since it typically dies on a blind curve on the off ramp and people can't see me unitl they are on top of me. Is there a fuel pressure release valve or anything that could malfunction? Any ideas?

[Scott McLellan]

I'm not sure, but is the fuel cap have some sort of valve or something that lets air in? Could it be that you were low enough on gas and when you went around the corner the fuel went to the outside and the pickup was exposed to some air or something? I don't know just an idea. Maybe if the fuel pump doesn't get fuel it shuts the engine down right away. I know my fuel level needle goes up and down depending on my driving. Other than that, you got me.

[mrFongMan]

i had the same problem before i chucked out the KA motor... the problem i had was electrical... i cant remember wat exactly.. i'll ask my mechanic friend he fixed it..

[nismo7]

thanks

[NISTECH]

try grabbin the wire harness at the back where it bends up to the rear wall of the engine bay. wiggle it and see if the car gets stupid on ya. could have a ground problem in there.

[nismo7]

I'll check that out and let you know. Thanks for the reply.

[bigE]

Sounds kinda like what I have going wrong with my car, at about half a tank of gas, the car starts cutting out in all gears as if I hit the governor, I fill the car back up and it goes away, had been happening for a while, now it happens earlier, I get to 3/4 of a tank and starts doing it. It's really same sometimes, pushing on the gas doesn't help it get more gas, just make it stay cut longer and cause it to kick back in harder.

Eric

[240SX=fun4me!]

My experience with two cars with the same problem (Ford Focus and My 96 Grand Am) is that it seems most likely a fuel pump and filter deal. My Mazda MPV has the same thing going on it, when the tank gets half or less, if i punch the gas after a corner she dies, give it a second to recop. she flys no problem. All three of these vehicles worked (will work=Mazda) fine after the fuel pump and filter were/are replaced.

Big E, your pump is goin most likely to, sounds EXACTLY like what happened to my Focus.

My Grand Am was worse, Pulled from a stop into a highway and my car died and didnt go again until pump was rplaced as well as filter. Be lucky that didnt happen to you guys...Yet.

[yellow_jacket]

Sometimes the tank actually goes bad. You either get a lot of rusty fuel or the feed for the bowl the fuel pump sits in will get clogged and the pump won't get fuel at lower tank levels.

[bigE]

My 240 has a brand new WALBRO 255 in it, so the pumps not going bad.

Eric

[91240]

Hey. Get comfy, this is a long one... Got the same problem, and I've read lots of other posts about it. I've had my '91 KA24DE for about two weeks. My problem has been unstable idle (hunts around from 400 to 1000 rpm, and stalling - both at idle and freeway speeds. After it stalls, it won't start for from 10 seconds to twenty minutes. Regarding the unstable idle I've seen posts on the cause being everything from MAF to tire tread wear (sorry, exaggeration to make a point). Not familiar with car yet, so took it to dealer (aka parts replacer). Mechanic did actually see it stall (forunately), twice. No spark (I had been ready to replace the fuel pump. This feels like a fuel prob to me.) Took his advice and ordered new coil/power xsistor. He replaced them, problem still there, so "You need a new distributor". OK, replace the dist - problem still there. HOWEVER - unstable idle problem GONE (crank angle sensor?). Now idle is rock solid and car stalls less frequently, but still does stall from time to time. Still reeeal suspicious of fuel pump. In my car I can hear the pump during the 5 secs it runs when you turn the key on, but its very quiet. Need the car to stall someplace quiet so I can tell if the pump's running . My question is; is the ECU sensing fuel pressure in some way, and shuttting off the spark, or; is there really an ignition problem. Any help would be greatly appreciated. I'll post what I find out.

[91240]

Oh, BTW, the previous owner had had the same problem, replaced the power xsistor and the prob went away. New power xsistr THIS time had no effect.

[bigE]

91240, it's probably not your fuel pump, Your problem sounds exactly like mine, it completely stalls out when I stop at lights and signs, doesn't stall at freeway speeds, but feels like a fuel cutoff when driving in any gear, and genereally when it starts in that gear, you can't go past that certain rpm that it keeps cutting out at, acting like a governor, unless you shift gears, then it starts all over again. I thought it was fuel related since everytime I fill the car up with gas, it's fine until a quarter of a tank then starts back up. I replaced my fuel pump and car ran better buit it still cuts out and cuts back on.

Eric

[91240]

Well, I guess its not exactly the same. Mine doesn't do the "governor" thing. Revs fine in all gears. Good to know about the fuel pump tho'. Knock on wood, but mine has been much more reliable since the dist and transistor went in, although it did die about six times in a hour shortly *after* the new parts and after it had warmed up. Its now Tuesday night and its only quit once since mid-day on Saturday. Arrrgh! I'm wondering if the stalling and the rev-limiter effect are separate problems? Thinking outside the box for a moment, does the rev problem happen when you're going down a hill? I'm trying to think why a tank fuel level might cause starvation. Anybody with the stalling problem (an there seems to be lots) ever put a pressure gauge on the fuel line to watch what happens? I was trying to find one the other day and all of the EFI guages (ie over 16 psi) are mechanical. Reluctant to bring fuel into the ****pit! Hmmph. Like I always say; everybody needs a hobby...

[nismo7]

great feedback guys, I have been suspicious of the fuel pump but my local garage felt that if it was going to fail it usually just goes all the way. I do tend to hear a whining sound from the rear like a slight buzzing sound (fuel pressure regulator) for about five seconds ever now and then after highway use and lower gas levels. Like I stated in the original post, the engine started back up (and yes it was like hitting the govenor when it did this) it went away as soon as I released the pressure from the gas cap?? I also have a rough idle but have replaced the dist, plugs and wires. I plan on doing the removal of the AIV as discussed in one of the other posts. I still haven't had a chance to check the wiring on the firewall as stated earlier.

[bigE]

I tried releiving pressure by removing the gas camp and it seems to get worse. I was thinkhing on my car, we bumped up the timing to I think 24 and I'm gonna drop it back down tommorrow and see what happens.

Eric

[240SX=fun4me!]

Try checking filter? Big E, who put in your fuel pump? I had the focus done 3 times at the same shop after it died once, and the shop put 3, yes count 3, with the wires on BACWARDS!

Just a thot, cuz the pump acted the same way each 3 times after a week, and it anoyed(and cost) way too much.

[91240]

I had tried taking the gas cap off when I found out about the vacuum relief valve - had no effect. Still could not start the car. The fuel pump is supposed to run for five seconds after you turn on the ignition (before you hit the starter). I'm waiting for the engine to stall in a quiet location, or when I'm with somebody, to check to see if it does. Its now Wed morning and the car has only quit once since Sat noon. The idle has dipped a couple of times, but not low enuf to stall. I hate a problem that seems to go away by itself. For the record, I also dumped a couple of cans of injector cleaner into the last couple of tankfuls of fuel. I'll be interested to hear about the results of the AIV removal. I have read that these things get gunked up mess up the mixture. As I understand it, they are only there to help the cat warm up faster. Not a problem to remove it if you never plan to have the emissions tested on a cold engine. So far replacing the dist seems to have cured the idle hunting issue. BTW - my ECU is reporting a leaky injector that I haven't had time to explore yet. Need to check to see if that prob is still there - I've used the injector cleaner since the last time the code was read. Hope to do that this weekend, also pull the plugs.

[bigE]

With the WALBRo, I can hear it turn on all the time, and I can hear it run for a couple of seconds after the car dies on me when I stop. Wires are on right.

I'm thinking I might have a bad cell in my battery possibly causing it, or a bad ground somewhere. Or possibly timing is advanced too much, I'm gonna try setting it back a little.

Eric

[Scott McLellan]

Maybe have your alternator tested. This problem might not even be fuel. When I had an alternator go out it would die and then when it did start the idle was all jumpy. Some trips there would be no problem, and sometimes it would just die with no warning. Just an idea.