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Discussion Starter #1
So, I had my idle nice and perfect for awhile, then just before Christmas it was back up around 1k rpm's. I figured it was because of the temperature. Well, it got a little worse. It developed a hesitation. As soon as I'd touch the gas the idle would drop back down to normal then build back up. Yesterday, any time I'd let off the gas then reapply, it would hesitate.

So, the last two nights I decided to figure it out and fix it.

2 nights ago I pulled my air regulator, tested fine. So I cleaned it out and the contacts, then replaced the connector. Car drove the next day(yesterday) but not any better. Last night I pulled the FICD and the AAC connectors, cleaned the contacts on both units, and cleaned the AAC connector(the FICD connector is new). While I was at it, I cleaned the throttlebodies and adjusted the TPS to .43 volts. I pulled the negative battery terminal for 10 minutes. This morning, I tried to start it. It immediately fired up, then just as fast died. Turned the key again and it will just crank but not fire up. I've checked all the connectors. Everything is connected. All the contacts are clean. I wasn't able to check the resistance on the FICD valve(bad angle), but everything else is within spec.

Other things that have been replaced: New coolant temp sensor and connector. All injector connectors are new. All injectors are within spec and have new pintle caps, cleaned filter baskets, new upper and lower O-rings and insulators). Bypassed the knock sensor. New fuel filter, spark plugs(PFR6B-11B), air filter in the last year.

No ECU codes. I can smell fuel. All coil pack plugs are on tight.
 

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Discussion Starter #3
I believe so. PTU has also been relocated.
 

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I didn't see fuel pressure reg or dampner in the list. This could be causing the fuel smell. Also agree with others chasing the spark. As far as when it was running, it sounded like a vaccume leak by your description of symptoms.
 

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Discussion Starter #6
Swapped damper for a known working one. Tested fuel pressure and it is within spec.(same time as injectors).

I'm kinda thinking vac leak now. But it must be a massive one. I pulled the AAC connector so that I could adjust the idle properly. I finally got the thing started, but iw was fluctuating between ~600 drop down to ~50rpms, jump back up to ~600 then drop. I tried turning the screw and it died. Couldn't get it started up again, had to leave for work.
 

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Discussion Starter #8
Usually yes... but not always. I had a bad MAF on my Z31, wouldn't start. Ballistic had the same problem.
 

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A bad MAF sensor should throw a code.

Pull your plugs and make sure they're not fouled.



Post Edited (Jan 5, 1:42pm)
 

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Discussion Starter #10
Is there a vacuum line at the back of the engine somewhere? Close to the rear driver side cam sensor, FICD and AAC connectors? I got it running, but it was VERY rough, reconnected the AAC and moved the wires around, after fiddling in that area got the idle somewhat stable around 1100 rpms. Still rough though, almost like it's missing. Maybe I've just fouled the plugs... Any ideas?
 
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