benZVHT

Hi all. My ZVHT Fiesta has got an annoying running problem & I'm hoping someone might have some suggestions!
Basically it's started holding back/hesitating from about 2000rpm. It does still go but it's def hesitating badly.
I have got a new Throttle Pot, changed plugs, checked everywhere for air leaks & still no change. Also tried running it temporarily with MAP sensor disconnected but hesitation was the same.
I have 2 stage boost & temporarily tried it on high boost, really didn't like this! Barely responded when I put foot down & sounded like a machine gun out the exhaust! Kind of similar to hitting rev limiter.
It had an MSD chip (OFAB ECU) & setup etc done only around a 1000 miles ago.
Any suggestions of what to try next would be much appreciated!
Thanks muchly.

BigJim19

have you changed the leads?

benZVHT

Nope, not tried the leads yet. They aren't very old, i.e a couple of years but I'll perhaps give this a try next

BigJim19

i had a misfire prob on some relatively new leads, changed everything, leads were the prob......

worth a try, you can get some from msd on ebay for £30 - bargain!!

benZVHT

Cheers mate, I shall give the leads a try next. My first port of call was the throttle pot, £36 later & it was the same! Another £30 can't hurt. After that it may be a conveniently placed match to go with the tank full of fuel I'd just given it!
Cheers

benZVHT

Getting desperate now!! If anyone has any other suggestions on this I'd really appreciate it.
Tried leads & coil now, still the same. Starting to think it's possibly a fueling issue? Checked the boost guage & is reading a constant 7psi (as it should) when accelerating even tho it's hesitating/holding back really bad.
Temporarily tried high boost & it amplifies the problem & mis-fires real bad. Also on over-run it's popping & banging like a good 'un...does this indcate running lean?
I've checked everywhere thoroughly for air leaks, nothing.
I have got a fuel pressure guauge so was considering whacking that on to see if it tells me anything useful.
I did also think about the map sensor but not sure if these are classic syptoms or not?
Thanks very much.

jb 3 door

take your fuel pump out and remove fuel damper between pump and sender unit,(small round about size off 50p)leave out and just replace the piece the small fuel pipe,that should sort it

benZVHT

cheers for the reply mate, i shall give it a try!

benZVHT

For anyone who's interested, found the cause of the problem was the bloody fuel filter! Old man, who's worked on Fords for about 200 years said he could barely remember a feul filter causing a problem of this type, it's only been on there for about 3000 miles
I'm about to go out & make the car suffer for costing me best part of £100!
Cheers.