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I have a 1990 honda civic automatic transmission and im having problems with it running.

when idling it runs fine, when pressing on the gas in park it runs fine. once i start to drive it it starts to run like crap, there is no power, the whole car shakes.

and ideas on what to check would be great.

 
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SWAG: Ignition parts. Plugs, wires, cap and rotor, that sort of thing.

 
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if it had to do with the spark wouldnt that affect it when it starts or when its idling?

 
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Not necessarily, depends on what the problem is.

Secondary leakage is most noticeable under high demand (load). Starting/Idling the engine is not a high demand condition.

 
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so i have started to look for the problem, I noticed spark plugs are in okay shape, the rotor under the distributor cap is definetly showing signs of ware some with the contacts on the cap.

I pulled each spark plug and hooked it to the wire turned it over and it appears they all have good spark.

so next i disconnected one wire at a time, turned it over and pulled the spark plug one at a time. 3 of the spark plugs were wet with fuel. the one closest to the distributor cap was dry.

so im thinking its not getting fuel.

could that cause the car to run fine at idle but run rough when in drive?

i dont see a fuel rail or injectors? im guessing its somewhere under the intake mainifold?

any thoughts would be great.

Thanks

 
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This is throttle body injection. 2 fuel injectors mounted in the side of the throttle body.




The other choice would be this type of intake with 4 individual injectors:




The dry one is probably the only one that WAS firing.

You say the other 3 are wet, were they wet with gasoline? Coolant? What?
Not my suspicion yet. Your plugs wet with fuel says you have fuel.

By design, TBI can't starve only one cylinder.

How big a gap can the spark jump? It needs to be able to jump a far wider gap than a spark plug has. It needs to be able to jump 3/4 inch gap or more.

 
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ya i realized after that its TBI, Ive never worked on anything like this. have only worked on vehicles with fuel rails with injectors.

they were wet with fuel, one spark plug had a bit of oil on it

i didnt check how far of a gap. i just pulled them out and turned it over and saw spark a the plug

 
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Do this.

 
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i havent checked how far of a gap yet because i need somone to turn it over for me but i did start it up this morning and pull each spark plug wire off one at a time and it started to run rough on each cylinder.

isnt that a sign that the spark plugs are working properly?

 
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Ok then yes. That's a cylinder contribution check of sorts.

I guess I didn't realize it would still run. I figured it wouldn't since you said you had 3 wet plugs.




But it still misfires on acceleration or under a load?
I would want to see how much spark is available to each plug (gap test), and figure out which cylinders misfire when it does act bad. Then figure out why.

 
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Check for evidence of carbon tracking, this is spark leakage. Sorry, I couldn't quickly find a good pic of a bad cap.

 
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there is definetly evidence on the inside the distributor, the 4 contacts have signs of wear as does the rotor its self

when i checked each cylinder for fuel i pulled the spark plug wire off the spark plug then turned it over, so it wouldnt fire and i could see fuel. thats why i thought it was weird that the one spark plug didnt have any fuel on it.

 
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I don't have any idea what made you think that...

Ok, wait. You were backpedaling when you don't need to.
The engine will run on all 4 cylinders, and each cylinder was firing as proved by disabling (pulling) one spark plug wire at a time and each one resulted in a drop or stumble.
This proved each cylinder has air, fuel and spark (at idle).
Stop.
TBI cannot starve one cylinder without affecting the rest evenly.
You said you have a misfire at higher RPM, not that it dies completely.
If my interpretation of your terminology matches.......then you do not have a fuel delivery problem.


You need to keep concentrating on the spark, or loss of it. The dist. cap is a good start.

Cap and rotor, plugs and wires are where I would either be looking or just replacing the whole bunch.
Not super expensive IMO and probably faster than guessing at individual parts.


Use the correct NGK plugs please. They are no more expensive than the wrong plugs.

 
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just under a load, when i accelerate in park or netrual it just revs up like normal

 
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Then this is still my suggestion:
I bet it actually will misfire if you suddenly snap the throttle to wide open briefly instead of slowly revving the engine up.
The snap action loads the engine a lot more than slowly revving it up, but still not as much of a load as driving it.

HTH

 
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i replaced just the plugs and its running like it was before it started to miss. there is still a bit of hesitation but it was like that before and its running good enough to be on the road

 
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Can you READ the plugs, see how the firing ends looked? That can give a lot of info to someone that can use the info.

Any plugs look like this?:

 
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so im back to figuring out why this isnt running like it should, i replaced the spark plugs which mad a difference but its not perfect.

the wires dont look bad, at least i cant see any bad signs, on the plugs or wires

apperently the car runs fine when its cold then once it warms up it starts to have this problem?

could that be anything specific?

 
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Had to review the thread, the descriptions of the problem are still kinda vague to me and make me think of several different areas. I think you kept saying it was a misfire at higher rpm. I guess I was thinking this was a misfire due to ignition breakdown......maybe this is just starving for fuel under a load instead?

Can you prove that by adding fuel manually from a spray can of carb&choke cleaner when it starts to run bad?? (if it will run bad while sitting still.)

Can both injectors squirt fuel? Is one plugged up? IIRC, this uses one injector all the time, and the secondary injector is for supplying extra fuel when under a load. Do both work?

How about checking fuel pressure?

 
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ya it seems to misfire at a higher rpm,


how can u check that the injectors are working?

 
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I can't say I have ever truly messed with one of these. Too old to show up at a dealer now, and I haven't been in a Honda dealer all that long.


#1 check fuel pressure. Check not only "by the book", but take it on the road and read what is happening when under a load and running poorly, even if that means sticking the gauge to the windshield with duct tape.

#2 if you think it is starving for fuel and needs more, squirt spray carb and choke cleaner in it while it runs bad, see if that improves anything (briefly). That would at least prove it is a "lack of fuel" problem and you are on the right path (or not).

I'll GUESS
Visual: Grab a flashlight, look down in the throttle body with the engine running. Can you see a spray of fuel coming from one injector?
Swap plugs for both injectors. Does the other one spray now? (will it run at all, even badly?)?

I might manually power the fuel pump and manually pulse each injector using a fuel injector tester (pulse timer), while watching what actually happens on the important end.