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96 1.0 won't start unless accelerator depressed?
Topic Started: Sep 20 2013, 10:55 AM (875 Views)
cwheel
New Member
[ *  * ]
I've had my 3-cylinder 96 for a year now, and love it, but it's had some issues recently.

1) A few months ago, it would randomly maintain a high idle (2500 rpm) at stop lights. I could turn it off, immediately turn it back on, and it would idle properly.

2) A few weeks ago, while taking it out of gear to shift at about 30 mph, it died. Was able to re-start it no problem and that was the only time it did this.

3) Also a few weeks ago, when not in gear, the RPM would rhythmically go from about 1000 rpm to 2500 rpm and back down again, about once every 2 seconds.

4) And last week, it will no longer start like it used to. It sounds like not enough gas is getting to the engine (almost like only one cylinder is firing), but as soon as I depress the gas pedal while cranking, it will start up fine and rev fine. But letting it drop back to idle makes it die.

Spark plugs are firing fine.

Any guesses where to start looking? Throttle position sensor?

Thanks!

-James

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JADEDSL2
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Resident WraithSlayer

If you have spark, air, and fuel, then start with TPS, and maybe ISC, MAP, IAT. Make sure all your car's computer's inputs are clean and functioning properly for starters.
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jeremy_nash


Check engine light on? If so, get it checked out for free at an auto parts store, then go from there.
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truckjohn


I am having similar issues with mine now....
First set of checks is the fuel pressure....
Does the pump put out enough pressure deadheaded (If not - check/change fuel filter and re-check) If the fuel filter doesn't fix it - bad fuel pump....

If yes - do you get enough pressure when it's hooked up to the Fuel Injection system.... If no - then you start checking through fuel pressure regulators and injectors in that order...

I wouldn't start throwing parts at it - as you can spend a fortune on parts and find out it was a loose connection or bad hose somewhere....

Thanks
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cwheel
New Member
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Thanks for all the help to date! Some updates: I don't have a lot of testing equipment, but I did win a $10 auction for some spare parts (TPS sensor, fuel injector, manifold pressure switch, etc), so I was able to throw some parts at it as a first step (no guarantee they were working parts).

Anyway, I'm wondering about my heated O2 sensor. I am able to start it with throttle wide open. If I keep the throttle up for about 2-3 minutes, I can then let it idle down to normal. It will then drive perfectly fine (and idle fine) for about 4-5 minutes. Then it stalls at idle from there on. I have a 95 service manual, and it says that surging of the throttle can be because of an O2 sensor (I was experiencing this before the non-start issue). I'm also thinking that maybe the O2 sensor is allowing idle only at a given temperature range, which is why it runs like a champ for 5 minutes in a "semi-warm" condition.

Anyway, don't have the ability to test mv cycling of an O2 sensor, and am considering replacing it IF you guys think that it could be a possible cause. If there is no way that a bad O2 sensor could prevent proper starting, then I won't bother.

thanks for any additional advice!

Oh, and I don't have an O2 sensor code, but when I connect my scanner, it does show 4 "old" codes (which I believe are stored on the scanner, or maybe the ECM), and they are EGR (which I knew about), misfire, and O2 sensor.
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patrickbruce
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average teenage gearhead

You need to figure out the misfire and O2 sensor..... Those are probably contributing
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