Engine "hiccups"

[TominMO]

When driving down the hwy, my 90 EFI 5-speed will hiccup from time to time; like it is cutting out for a fraction of a second. I'm thinking either partially clogged fuel filter, or maybe the electronic module in the disty is a little flaky. What do you think?

[fastivaca]

I had similar problem at times. Once it turned out to be bad plug wires, another time was a loose ground connection close to the distributor and yet another was badly fouled plugs.

[TominMO]

I had similar problem at times. Once it turned out to be bad plug wires, another time was a loose ground connection close to the distributor and yet another was badly fouled plugs.

Plugs are new, plug wires nearly new. What sort of ground connection, a ground for what?

[Pu241]

I could also see this being caused by corroded distributor cap contacts.
I clean mine up every now and then, with a brass brush.

[mattswabb]

Agree, it's probably the cap and rotor. Clean it up or buy new.

[Pu241]

Hit the rotor with the brush while I'm in there too!

[TominMO]

I could also see this being caused by corroded distributor cap contacts.
I clean mine up every now and then, with a brass brush.

I'll look into it. They are pretty new, too--cap, rotor and wires all put on by previous owner just before I bought it, maybe 4000 miles ago. I'll also report back what brand my parts are; you can tell me if they are good or junk.

[TominMO]

Pulled disty cap; quite corroded on the four terminals. Cleaned 'em off. Rotor looked good. We'll see if this makes the difference.

[mattswabb]

4000 miles on a festiva rotor is a lot of miles. I always cleaned mine a few times a year.

[TominMO]

Yep, cleaning the distributor contacts did the trick. Took it on a mileage run today and it didn't cut out even once! Thanks guys.

[benms79]

When driving down the hwy, my 90 EFI 5-speed will hiccup from time to time; like it is cutting out for a fraction of a second. I'm thinking either partially clogged fuel filter, or maybe the electronic module in the disty is a little flaky. What do you think?

sounds kinda like what mine is doing hmm,i should check it out,but mine will sometimes act like it wont take gas,if i cut it off and sit for a sec,it will go back to normall.

[clintorino]

i have the same issue when on the hwy. I changed my dist cap, plugs and wires last week and mine still hiccups.... any other suggestions?

[TominMO]

i have the same issue when on the hwy. I changed my dist cap, plugs and wires last week and mine still hiccups.... any other suggestions?

Try sneaking up behind it and scaring it. :-)

Tell us about your car: carbed/EFI, auto/stick, year, etc.

Basically there are only four aspects to an internal combustion engine: air, fuel, spark and timing.

It is probably safe to say it's getting air if it runs at all, but it never hurts to check the air filter. I bought a CRX w/42K miles on it with what had to be the original air filter! Gas mileage doubled when I put a new one in.

Timing isn't usually an issue; the distributor timing doesn't really change, and the valve timing should stay the same unless a belt got stretched and jumped a tooth or two.

So that leaves fuel and spark, the most common culprits in engine-running problems. Most likely the task will be to narrow down which of these it is, and then get to the exact problem within fuel or spark.

Fuel:
In a carbed car, my experience with fuel filters is that they need to be changed every 10K miles or so. I always kept a spare in the car, along with the tools to change it out. Had to do so twice on road trips, far from any McParts place; saved a lot of hassle. Other things to check are the fuel pump (nice to have a spare one of those too); the carb itself may need rebuilding, or at least cleaning of the jets with a good fuel additive. I like the kind that cleans carbs, fuel injectors and the combustion chamber. There could also be some emissions device that is not working.

In a FI car, it's pump, fuel injectors, filter of course, and the MAF or VAF. I can't go into too much detail on all this because of limitations in my experience with these systems.

Spark:
Juice getting to the coil? Getting to the spark plugs? Check the basics first: plugs gapped properly, plug wires firmly connected at both ends, coil wire firmly connected at both ends. Rotor in there all the way? Cap has no corrosion on the four contacts inside? No evidence of arcing between the contacts? If all this seems good, then maybe look at swapping in another coil, or the ignition module inside the disty. Your miss may be evidence one of these is on its last legs.

That's all I got. Others please chime in with more to fill in the gaps.