Stutters above 3K rpm.

[stecad]

After 2 years of rebuilding I've finally got her back on the road and she runs lovely until I put my foot down. Once she climbs above 3000 rpm it's as though the fuel is cut and the car stutters. I've not really pushed it hard to see what it will do if I keep the throttle to the floor.

During the rebuild I had the ECU checked over as it has the batch number that is known to be faulty. It was given a clean bill of health.
The previous owner had changed the fuel pump to one in the boot which was making some strange noises (bag of spanners) so I changed this to one recommended by TCB. I've also changed the fuel regulator as this was suspect (looked cheap & nasty).
I'm thinking that I rip out the whole fuel system over the winter and return it back to stock as the retro fitted system just looks pants.
Any thoughts to get me going to catch the last of the summer.
Cheers
steve MKII, Rev II.

[Ryan S]

check air flow meter, I was gonna suggest fuel pressure but sounds like you have that sorted. AFM can cause (or at least did for me) similar problems. Also check plugs and lambda sensor.

[markstevieandmads]

Is the coil cracked? Whip it off and make sure the bracket is clean as it earths through it

[Ryan S]

Is the coil cracked? Whip it off and make sure the bracket is clean as it earths through it

another good suggestion. I have a spare coil/igniter and bracket here if you're stuck.

[androo007]

I assume there isn't an engine check light that appears. Usually knock sensor light kicks in at 3 when blown

[stecad]

Many thanks for the suggestions. I should have said I went for the AFM - checked the resistance across the terminals and they were all in spec.
Not noticed any engine lights, but i'll check the knock sensor and the coil.
Steve

[androo007]

If the light doesnt permanently illuminate at 3k rpm it won't be the knock sensor.

Most likely ingition related. Check the ignitor isnt cracked.

[stecad]

Many thanks. New coil on order. The leads, cap and rotor arm are all new as part of the rebuild. The distributor was cleaned and checked during the rebuild. The current coil is the original and I'm sure tested OK but who knows what happens when it warms up and is under stress. Seen similar on other cars I've owned. I'll update at the weekend when I change it.
Cheers
steve

[stecad]

Update - never assume that the previous owner knew what he was doing. Matched the Fuel pressure regulator plumbing to pics taken during strip down. Replicated this for the new FPR but was perplexed that pressure gauge was not showing anything despite car running.
The previous owner had also rewired and re-plumbed the fuel pump to one in the boot with services that I've yet to get my head around.
Switched the pipes around and pressure gauge works and no stutter at 3K rpm. Happy days.

[Ryan S]

Excellent!!