Hesitation Problem

[judE30]

Guyz, i having this hesitation problem with my E30 M10 318i car.
It will appear at low gear 1st and 2nd gears most of the time.
Any solutions? common caused? pls.. thanks

[crazyman]

Can you be a little more descriptive please.

[SoopaGhetto]

car is running lean. check fuel pump and injectors. also check afm, and maybe vacuum leaks.

[crazyman]

^ not necessarily dude^ there can be allot causing a hesitating problem. Plus if it is just a fuel issue it will be more pronounced in higher gears where there is a need for more power (fyi more fuel flow needed basically). Plus its really hard to try and diagnose a generic hesitating problem when that's all we know, it needs to be more descriptive, like rpm range, speed range, how he is driving it when it hesitates such as grandma driving, easy driving or driving it like he stole it. With out being there and hearing it, it is nearly impossible to diagnose it based on that simple description.

[SoopaGhetto]

^ not necessarily dude^ there can be allot causing a hesitating problem. Plus if it is just a fuel issue it will be more pronounced in higher gears where there is a need for more power (fyi more fuel flow needed basically). Plus its really hard to try and diagnose a generic hesitating problem when that's all we know, it needs to be more descriptive, like rpm range, speed range, how he is driving it when it hesitates such as grandma driving, easy driving or driving it like he stole it. With out being there and hearing it, it is nearly impossible to diagnose it based on that simple description.

i was just kidding. not enough info to necessitate an exact diagnosis.

also, you have more load at lower gears (more power needed), light load in higher gears (less power needed). this is going from a stop, accelerating, then cruising. WOT is high load in all gears

vacuum leaks, under load youll get hesitation, cruising not so much.

i can list more of what causes hesitation, i figured those would be easiest to check.

[judE30]

Actually, it will hesitates if i suddenly step the gas @ 1st and 2nd gear, 2-3k rpm. sometimes it also appears at 3rd-5th gears.

[hahaitzskippy]

ok imma hijack this thread

i am having the same issues

i just had teh fuel filter cleaned and the fuel injectors cleaned out. now the hesitation is worse.

i am sure i do not have a vacuum leak because my idle is spot on but at times it revs up and holds. never pass 1200 rpm though.

i was planning on replacing the fuel pump next.

what is the AFM? how do i check that?

if i clean out the ICV would that do anything?

whoops forgot to mention, hesitation happens most apparent when cold. as if i am hitting fuel cut and car will not accel.

when warmed up, usually happens between 3.7-4.5 RPM. all gears.

[crazyman]

Sorry guys I have been working all week. What I would do if I was the both of you, I have done this myself and it won't hurt the car. When I was having pretty bad hesitations I traced the vacuum advance line for dizzy cus that's the only thing I hadn't messed with, well long story short I never found a way to test it but there is a inline electronic piece that electronically controls the vacuum advance (probably for emission purposes). What I did was unplugged it and pulled it out and ran a vacuum line from the dizzy straight to the intake for the vacuum advance to work. After I did that and a complete tune up my hesitation went away, also got more power and better throttle response as well. Do that and let me know how it works.