Hesitation when accelerating

[Caleb]

Bought a 91 festiva "sport" a while back, it started running sluggishly and lurching when trying to accelerate and the water pump started leaking the day after we bought it. So I replaced the timing belt, water pump, spark plugs and wires, fuel pump and filter and ran a can of seafoam cleaner through the tank. The sluggishness went away after the new plugs and wires but I am still getting the occasional lurching on acceleration. The old fuel filter was disintegrating and causing issues I think, the new filter has caught quite a bit of sediment already. I dont think its a blockage in the fuel rail because the whole engine drops for a second, not just one or two cylinders at a time. I am going to change the distributor cap when I have a chance although the current one looks brand new... Anything else I can/should check?

[SurgErick]

Check your air flow meter there's a really good and very detailed article at the bottom of the forum page called "air flow meter matienance".

[mikemounlio]

Your dizzy cap is bad and needs replaced

[WmWatt]

Check for sediment in your gas tank?

[ryanprins13]

Is this a 91 carberated?


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[Ninjawimp]

Fuel filter sitting correctly N not upside down? Ive done it before lol

Is the fuel pump sock similar to the stock sock? If the meshing is too close it might be restricting fuel to pump

Recheck spark plug wires to confirm they are in correct firing order.

You can also pull your new fuel filter & blow through it to see if there is any blockage




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[Caleb]

Well my internet crashed and I lost my long winded reply so...

It's a 91 or 93, cant remember but its injected.
fuel pump sock similar sizing, filter in properly, there was small amount of sediment in tank; consistency of flour and very little of it.
The hesitation is quite rare after changing above mentioned parts and I think it may even just be sediment on the engine side of the filter working its way out of the lines.

I looked at the dizzy cap a little closer and it has a cracked rubber seal(not as new as I thought) so thats #1 to replace, #2 is a teardown on air intake sensor.
I'm trying to avoid spending any more money on this car...

Thanks for all the suggestions guy, I really appreciate the input!

[Caleb]

Another update:

So I took the car for a nice long test drive and it only seems to hesitate and stutter at "lower"(anywhere up to 3000?) rpms if I try to accelerate quickly with my foot to the floor. If I redline when I shift and slowly press down the pedal there is barely any hesitation. The biggest problem is putting my foot to the floor, even driving at 120km/hr it will bog down and not really recover until I downshift into 3rd and get my rpms back up again.
I pulled apart the dizzy cap and everything looks brand new, tiny bit of corrosion on the rotor but I sanded that off easily. MAF is the next thing for me to check but wont have time till late next week and my sister is driving the car to work... or trying to.

any ideas?

[WmWatt]

Not supposed to sand a platinum rotor because it removes the thin coat of platinum. But then would a platinum rotor rust? I recall "overhauling" may distributor cap and ruining it because it was platinum (coated) contacts. Had to buy another.

[Caleb]

Today I pulled apart the VAF and it was pretty clean and everything seemed to move very smoothly and easily inside. The only thing that looked questionable to be was this little doodad that looked oily, not sure what it does...


I cleaned out the fuel filter and blew through it easily. There isnt a second filter hiding somewhere else on the car other than under the hood is there?

I loosened my distributor and rotated it both ways, one way lowered the idle and the other way raised the idle but it still bogs down and will die if I move the throttle all the way open and hold it there under any distributor position. Even opening the throttle fairly slowly will stall the car now. It seems to be getting worse. Could my timing be off one notch and cause this problem?? I don't have access to a timing light till the weekend. It was running fine a couple weeks ago though so I really don't know.

Also, this "fuse?" is really corroded, could that be causing issues??


Is it worth trying to get a fuel pressure tester and double checking my pump is working properly? It seems strange that the car was running great and now is getting worse and worse.

[Caleb]

1

[Caleb]

I also disconnected the O2? sensor just below the exhaust manifold while the car was running and it seemed to make no difference, is that normal?

Could this stalling engine be caused by a faulty fuel pump relay?

[Caleb]

ITS FIXED!

I pulled the fuel pump a few days ago and wanted to give a quick update. I screwed up and installed the fuel pump O-ring without the plastic spacer and over the next week the o-ring was slowly forced out of the housing causing less pressure to reach the injectors. Everything is running smoothly now.
I did also pull a bit of dirt out of the tank just to be safe. google "grit-gitter" and buy one if you have to clean your tank, I borrowed the one from our hot tub and the job was done in about 30 seconds. Now I have to think of an excuse for why the hottub smells like gasoline but that's still much easier than fixing a festiva...

Thanks for all the input!

Cheers,
Caleb