thrasherx

A year ago:
Symptom: About a year ago, the idle would occasionally drop upon starting.
CEL: P1456 (I know, probably unrelated)
Repair: First I replaced the IACV as instructed by one of my mechanic friends. After no change, I took it to my other mechanic and he showed me that I had a bad head gasket. He replaced it, re-planed the head, and did timing belt/water pump.

A few months ago:
Symptom: Gas fumes when the tank was low (<1/4).
CEL: P0171 (Bank 1 running lean)
Repair: None

Last week:
Symptom: Idle started surging on the way home from work (1000-1500 RPM in D/P, 1000-2250 in N). It's very sporadic (happened yesterday afternoon, but not at all today).
CEL: P0171, P1129, P1456, P1457
Repair: Looked for vacuum leaks by spraying carb cleaner on the vacuum lines. Started to remove MAP sensor, then changed my mind after seeing where the second screw was.

I've searched around, and found that most people recommend starting with the IACV. Since I changed that out less than a year ago, I doubt it's the problem. I'm not completely ruling it out, but would like to hear other opinions before I check it, since it's so tight behind the intake manifold. I know that all the CEL may not be related, but it's always good to have more info and background on an issue. The car runs great (other than the idle, and the occasional fumes). Ideas?

JamesB1985

I have seen a lot of Honda idle problems caused by air in the coolant system. Bleed the cooling system if possible.
Do you have decent spark plugs? I like NGK's.
Do you have new/good spark plug wires on your car?
How is the Dist. Cap?

Adjust your valves if possible also.

thrasherx

The coolant has been bled a few times. I have NGKs and a new distributor, as well as NAPA spark plug wires (<10k old).

I was poking around today, and I think I hear the 'hiss' of a vacuum leak. I can't figure out where it is. Maybe tomorrow. Thanks for the help!

reyray05

i have a similar problem, wen my 1990 accord is cold and idleing it revs up and down, (or high then low) til warm. i was once told it may be an erg issue. it still does it and i have no clue how to fix it. any suggestions?

Lost Again

For you, clean/adjust the FITV

thrasherx

No luck finding a leak

thrasherx

... And the car died on me (shut completely off, without warning), while I was driving home from work on Thursday. No CEL or anything. I installed a new distributor a month or two ago. It shouldn't need any adjustments, should it? The way the distributor mates to the camshaft, it seems unlikely...

xci9v8icx

did it start back up asap? or did it have to cool off, i had the same issue if it had to cool off for a bit and it was fixxed by replacing my main pgmfi relay the one the controls the fuel pump, and other main circuits, what happens is when the relay heats up the contacts start to seperate and thats why when it cools down it starts back up, uhm idle problem aswell was fixxed by cleaning out my idle air control valve, its simple to do, 2 or 3 bolts and 2 small coolant lines running to it just to keep it cool, i found the best way to clean it was taking a little bit of motorvac solution and just letting it sit for an hour or so, there is a can that kleen-flo makes called intake clean and it works exceptionally well also, check your distributor cap and rotor, just make sure everything is snug in there, also the connections inside the distributor should all be tight double check to make sure no wires are loose, if there are any just take needle nose plyers and pinch all loose connections together

thrasherx

Awesome advice, thank you. It started right back up, no problem. It wasn't too warm outside, and I had been driving it for 5 minutes.

I resoldered the solder relay on my 91 CRX a while back and it worked great.

I'll check the dizzy cap and rotor. TBH, I was surprised that it ran so well when I installed the new distributor. I was expecting some kind of adjustment.

Needless to say, I'll be glad when these issues get ironed out. My car has 203k miles on it, and I'm pushing for 300k.

Lost Again

And don't forget the key switch (elect part) does go bad. Key in the on position, check for voltage on the Black/Yellow wire going into the dist.