hesitation while accelerating

[formula driver]

Cars an 87 is. My car hesitates under acceleration. It's bad when its cold and when does it very little when the car is completly warmed up. What could this be? AFM? ECU?

-Paul

[JPL]

i'd like to know this as well.

[Garageaholic]

Check your reference and crank sensor on your tranny bell housing. Maybe something is grinding up against them that is giving it a bad signal. Slim, but possible. Also, your fuel delivery system could be faulty. Disconnect your fuel supply line and turn the engine and see if the amount of fuel you fill up in a measured bucket in a certain amount of time is up to spec (check bentley manual). If not, you may have a bad fuel pump. Also the fuel filter could be clogged too.

One last thing i'll suggest is the distributor/rotor. If it's failing, it will work just a little bit better when the car is warm than when it's cold, but not much. My bet is with worn connections on your distributor. Good luck!

[porsche gt1]

I am thinking it is your fuel pump. does you car take a while to start i.e. crank for a couple seconds before it turns on?

[Garageaholic]

shit, i dont mean to post after myself, but i've been thinking about it alot. If you have an exhaust leak before the O2 sensor, you could have really shitty emmissions. Is your mileage decreasing too? BC if it is, you could have an exhaust leak and that causes hesitation too along with a gurgling sound under cruising.

ok i'm done now

[formula driver]

I am thinking it is your fuel pump. does you car take a while to start i.e. crank for a couple seconds before it turns on?

Yea, it takes a second longer to start than normal most of the time. When its warmed up it runs great only bogs every once in a while. Its almost like a backfire...

Car just cuts power, and then its fine again. It seems as if its kinda fuel momentarily...

Thanks for the help so far guys, keep the suggestions coming.

-Paul

[PУCCKAЯ_e30ka]

if you have stock (never replaced) ignition wires... replace that! might be an ignition problem..

[Garageaholic]

it's either ignition, fuel, or electrical. Lol that narrows it down for ya! lol

[porsche gt1]

it's either ignition, fuel, or electrical. Lol that narrows it down for ya! lol

all you need now is something wrong with the chassis and you will never figure it out

[porsche gt1]

Yea, it takes a second longer to start than normal most of the time. When its warmed up it runs great only bogs every once in a while. Its almost like a backfire...

Car just cuts power, and then its fine again. It seems as if its kinda fuel momentarily...

Thanks for the help so far guys, keep the suggestions coming.

-Paul

If you have a bog while driving it might be your CPS as M3fan suggested as this would throw off the timing.

when my fuel pump was tarting to go it started out as a longer crank then I had to start giving it a little gas to get it to start. I hope it is something more simple like the ignition wires or distributor. They should be easier to test.

[325iCabrio]

it's either ignition, fuel, or electrical. Lol that narrows it down for ya! lol

I have the same problem, and I came to the same conclusion. In fact, my E30 cutout for about two seconds and then came back to life while I was cruising at a steady 40. :crazy:

In my case I'm pretty sure it's either the crankshaft position sensor or the fuel pump. My ignition wires are original, so they're also going to (eventually) get replaced.

Good luck Formula. This problem fucking blows.

[browntown]

fpr vacuum line?

[325iCabrio]

fpr vacuum line?

That's not a bad idea. I might check that out.

[mtechnik]

Have thw same thnig every now & then . I let p off the pedal and re-apply gas. My spark plug wires were replaced about 55.000km's ago

[formula driver]

if you have stock (never replaced) ignition wires... replace that! might be an ignition problem..

Wires are brand new red 8mm wires....not the problem.