zeejay

Hello everyone, I'm having some throttle issues with my 91 civic. I just got it for free from a friend, and I haven't had the time to talk to him about the car, he had it towed to my house last week and I haven't heard from him since.

Every time I hit the accelerator the engine sputters, almost as if the fuel injectors, or some fuel pressure fault was causing the fuel to delay initially. if I hold the gas down while it's sputtering, the engine will catch up to speed and run smoothly - usually backfiring in the process. it does this only when the engine speed is relatively low - sitting on low idle or shifting to a lower gear and going up hill after a sharp turn.

I spent all of yesterday tinkering with the fuel and electrical system, and I found no obvious problems with any fuses or wires; furthermore, when I turn the key to ON the check engine light comes on and you can hear the fuel priming for a few moments until it clicks and the CEL goes out, like normal. I haven't checked the main relay yet, though - I can't find it...

I also tried Seafoam, put a whole can in the tank thinking it was clogged injectors, or water in the fuel, but it didn't fix the problem. it made it run just a little better, but it still sputters every time I hit the gas.
The previous owner said he tried two other fuel and injector cleaners, other than seafoam.

Well, I'm going to tinker with it all day today, because I don't have a vehicle right now, and I'm moving in a few days, so I got to get this car running right.
Any help will be greatly appreciated.I'm not sure what I should check next..I was about to order new injectors. This Honda has the 1.5engine with two injectors placed vertically, brown above green. New ("cheaper") injectors will total $420. Damn.

ezone

If it was a main relay problem, it wouldn't run at all.



Car was free----had to tow it----"friend" goes into hiding----car has probably been sitting for a while? How long?

SWAG:
How old is the gas in that tank?
Old fuel can make any engine run bad, really bad, or even cause damage.
Additives can make it worse instead of better.

zeejay

Car couldn't have been sitting for more than 6 Weeks.
I talked to the previous owner, he said his evil neighbor siphons gas from his tank and may have added some weird crap. Whatever, it runs.

Tomorrow I am going to spray seafoam down the intake to clean out any build up that may be the problem.

I replaced battery and oil pressure sensor.

The guy at the auto shop said it may be the throttle position sensor, so I ordered a new one. Didn't ask when that will arrive.

Could this be caused by improper timing?
How about spark plugs?

The fuel filter, distributor, and spark plug wires are all new, and the fuel pressure was checked and found to be fine.

ezone

Everything on your list can be tested or inspected and evaluated before wasting money on anything.
Yeah, but it runs like dogshpoop.
Weird neighbor? Duh.
You did a fuel pressure test? You should have taken a fuel sample in a clear glass jar to see what comes out of the tank.
If it ain't straight gasoline, it ain't gonna run right.
Drain it out and get $5 worth of fresh gas if there is any doubt (I'd pull the pump and siphon or suction gun it).

zeejay

Replaced fuel filter, the old one had gnarly gas coming out;I also drained the tank - the samples I collected were contaminated with dirt upon extraction, because I wasn't exactly ready to empty the tank, but a clean sample I got didn't look dirty..

Car continues to sputter, but I think it may be better since I replaced the fuel filter.
replaced the air filter while I was at it, too.

I don't know what to do until my TPS arrives.. I think that may be the whole problem, because when I unplug the sensor the throttle goes nuts and sputters like crazy.

Thanks again for your help