gas cuts out occasionally, any ideas?

[redsuns3838]

for the past week i've been driving, sometimes WOT, sometimes cruising or just slowly accelerating, and all the sudden the revs start dropping and there is no response to the throttle. The car doesn't shut off instantly because this happens in gear, but there is no response when I push the gas pedal down. So I just put it in neutral and the car shuts off. I popped the hood and checked for anything irregular, checked for IC coupling leaks, loose wires, etc...nothing I can notice.

The car doesnt start up immediately but cranks fine. (my guess is because theres no fuel getting to the engine?) Usually after about 10 minutes of waiting around/scanning my engine bay for problems, I'll try again and the car will start up fine and drive fine.

this has happened about 3 times in the past 2 weeks, and its on a SR20 with mild mods, just IC, exhaust, intake, mostly the basics. Car runs well outside of this 1 little problem.

anyone have any ideas?

[projekt_s13]

Do you have a kill switch connected to the fuel pump signal on the ecu? This was happening to me, the wire going to the kill switch got sliced a bit and would touch the metal on the chassis. Car would start then shut off, I also wouldn't start in the mornings and if it has been sitting for a while.



Fixed the connection and boom no more problems.

[redsuns3838]

you know, I might have something set up with my alarm...the guy didnt do the BEST install ever...some things have gone wrong with the alarm. maybe it does have something to do with that but I'm just not too good with wiring and I havent been able to get in touch with the guy lately. Might have to take it into a shop =/

any idea what else it might be, some other things I can check?

[DJ_Sunrise]

Check the ECU for codes? Seems wiring or ECU related.. If it was a bad sensor, it would do this more often, no?

-Bart

[redsuns3838]

No ECU codes, 55-all good, no boost leak. I'm beginning to think its my alarm after it happened yesterday and my 2way alarm wouldn't respond when I tried to lock the car. I guess I'll have to get a re-install of the alarm to be sure.

[Z U L8R]

you might be having a problem with the ignitor for the coil packs, but i'm leaning more towards the cam angle sensor. that is what lets the ecu know the position of the cams/crank so the ecu can give fuel and spark to the corresponding cylinders. basically as a quick test you can hook up a test light to the POSITIVE battery terminal when the car's acting up, have someone crank over your car. unplug an injector plug and probe the injector plug with the test light while they're cranking it over, your test light should blink as they're cranking on one of the wires. one wire will get 12volts with key in ignition ON position, the other wire is the one you're checking to see if it's getting the ground pulses from the ecu. if your light is blinking as he's cranking then your cas is fine. then you can move on to see if you're getting spark. unbolt a coil pack, slide a spark plug in it and touch the bottom of the plug on the valve cover while they're cranking and if you're not getting spark then you probably just have a bad ignitor. these are steps for you to diagnose your problem. it's better to spend some time, and replace/fix one part, than to spend money replacing many. good luck, tell us what you find.
Dave =]

[twofortyrida1388]

I'll say fuel pump. Got a fuel pressure gauge? If not make one.

[redsuns3838]

unfortunately or fortunately, the problem happens so rarely like maybe once every week or two, and its always on the road or somewhere, I'm going to start carrying tools with me, but it doesnt happen enough where I can just test everything out in my garage.

I'm starting to lean towards crappy alarm wiring though. Last time it happened 2 days ago, my 2way alarm would not respond even when i held the pager right up next to the antenna. As soon as the car started half an hour later, after cranking every 2-3 minutes, the pager worked fine. I think it has something to do with wiring for a fuel pump cut or something.

strange thing is, when i gave it gas and tried to start the car, it would start for a split second, hit about 300, yes 300 RPM and die immediately. so I dont know. guess ill just start with testing FP and CAS and ignitor. car runs perfect otherwise though, so I dont know if it would have to do with ignition, im leaning more towards fuel right now.

[Z U L8R]

hmmm. i have a friend too that his car would just randomly die, and bog down, then if he turns his key off and back on it'd work fine, he replaced everything, relays, cas, ignitor, undid the turbo timer, none of that fixed it. he put another MAF on it, problem fixed. *shrug