Acceleration problem, advise needed.

[joseph cardone]

Hi there,

"Sometimes when I press down on the gas pedal after a couple seconds the rpms decrease as I keep a constant or increased pressure on the pedal. I have to take my foot of the pedal and press down on the gas again which inturn it happens again. if you have any suggestion I would appriciate it."

This post expresses a problem that is similar to what my 93 exr is experiencing. Except that it seems to go away around 4000rmps. Happens more frequent when humid. It's like all the cylinders are loose spark. It's like someone turned off the turbo, then without warning the car takes off like someone hitting the nitrious button. Also it only started after the it passed emissions.

It failed emissions the first time. The path for recirculating the oil vapors was block. So my mechanic cleaned all the gunk out of the passage. He also replace the cap and rotor. I replaced the sparks plugs.


My mechanic did find a fault with the cap so he replaced it but then the problem got worse.

Engine is stock. KN filter. NGK platinum plugs. Accel 150ohms/ft spark plug cables.

Things that we checked:

-spark plugs are new and good.
-cap and rotor replaced again.
-ignitor replaced, helped to make the problem less frequent but did not solve
-checked fuel pressure, good.

I have some thoughts on what it might be.

1. the ignition coil
2. the whole distributor assembly
3. EGR soleniod valve
4. 217,000km on the same fuel filter. My mechanic does not think its fuel related.

Any suggestions or advise welcomed.

93 exr daily driver

[b16a3sol]

i would start with the coil, then check the distributor. what resistance are the stock plug wires supposed to be at? if you dropped the resistance, with the wires you installed, by too much, you may have fried something by drawing too much current.

i agree with your mechanic that its most likely an electrical problem, especially since you have changed those parts, and he found a problem with the old cap. replacing the fuel filter just to be safe is never a bad idea, especially considering how many miles you have on that one. the other thing to do is get your injectors cleaned out.

[joseph cardone]

be looking at the distributor assembly and the coil. He got a rebuilt assembly that we can use to see if that's the problem. I will have him replace the ignition coil just in case. Fuel filter has already been purchased and I am waiting for him to install it.

I think the faulty cap my have damaged something in the distributor assembly.

The spark plug cables are just 150 ohms per foot. I kept the stock ones and put them back on the, but there was no change.

The old cables are roughly 14,000 ohms, whereas the accels are about 1400 ohms depending on the length of the cable. I took some measurements with an ohm meter and compared them. I wrote it down somewhere. Lower resistance cables make a noticeable difference, not to sure how that would affect the ignition coil.

93 exr daily driver

[b16a3sol]

if you draw too much current through it, you will cause the wires to heat up, possibly frying them out. the coil is meant to create a very high voltage, but very low current, ideal for creating a spark in your motor. too low a resistance could cause too much current, risking burning out key electrical parts. this is just an idea though, as i dont know what your real problem is.

[joseph cardone]

I guess it depends on how they designed it. If the wires are rated correctly. I don't think there would be a problem. However, using ohms law we can find out how more current we actually got. I think the icrease in current would be more detrimental to the cap and rotors (means replacing them more often) electrical conductors compared to the ignition coil. I think there maybe to much current for the distributor assembly. I am not saying the ignition coil is not the problem. All I am doing is following the flow of currrent. The distrubtor assembly went in today. A brand new unit. I will find out if that cured the problem. Otherwise, the ignition coil is next which is the supply.

I am checking the distribution of the electricity. Then I am checking the supply. May be backwards. But I am wondering if the defective cap damaged the distributor assembly.


93 exr daily driver

[lorunner]

its a 93 accord? and you have a stumble on acceleration? Is it an specific rpm? Just trying to gather more info on exactly what the problem is.

[Igovert500]

Just stating the obvious, but did you check the gap on the plugs?

[joseph cardone]

The car stumbles from start to about 4000rpms. Then the problem goes away and the car takes off like someone hit the nitrious button. No engine codes. The problem is not constant. More apparent when humid. I have replaced the spark plugs with NGK platinums and gapped them according to the Haynes repair manual.

93 exr 5 speed

[lorunner]

ok those cars have a known EGR problem were the EGR ports in the intake get clogged and that will give a stumble pretty similar to that of arching wires but that happens around 1800rpm. i never really saw one that had it at 4000rpm but i gues anything is possible. Just a thought.

[joseph cardone]

I still think it's EGR related myself. The distributor assembly was replaced. The problem still exists. Next step ignition coil. Then if the problem is still there replace the EGR valve and/or solenoid.

I put back on the old spark plugs cables back on the car and still have the problem.

Only two item were changed.

1. The cap, which was defective. The has been taken care off.
2. The EGR path was cleaned to have the car pass emissions. That I will work on soon.

For now I will replace the ignition coil and see what happens.

93 exr 5 speed.

[joseph cardone]

Two of the three wires to the egr solenoid were shorting to each other.

Problem fixed.

93 exr daily driver