Fixed misfire, now flat as a pancake !

[nick200]

Hi,

Car pulled really strongly until high load high rpm when I got a bad misfire.

Decided to target the ignition system, found two open circuit leads.

So replaced leads, new plugs ( ngk iridium as before ) and new distributor cap.( nipparts )

However although the car starts fine and idles smoothly, it's flat and significantly down on power.

Any ideas ?

I have not checked the timing since only replaced the cap, but wondering if there is enough tolerance in the cap fittment to throw out the timing ?

Also there was no visible rubber dust seal I have read about, is this necessary ?

The other part I removed was part of the throttle body to gain access to the spark plugs. This had no gasket which seemed a little strange , too ally faces ? Does this sound right ?

Any thoughts, appreciated.


Rev3 1993 turbo. Apexi afc + blitz boost controller.

[platmatt8]

I presume you can hear the turbo spooling up and you have boost?

My REV 2 has a thin metal gasket between the throttle body and intake manifold, it sure what the rev3+ has.

[nick200]

Thanks mat for reply, I had some boost but have found not enough boost !

In the end I tracked down the fault to a kinked vacuum/ boost line to the boost controller. Basically I was maxing at 8psi on a temporary analogue gauge, and the boost controller display read 0.

It's a blitz controller and I wonder if it recognised a fault condition and didn't try and modulate its valve. Potentially it could have massively overboosted since it would never see a reading.

For completeness, the other issues I mentioned:

Distributor cap rubber o ring seal: , this was stuck on the engine side - so it was there but had never noticed it.

The throttle gasket : there are several parts to the throttle housing and this is one section that connects to the inter cooler piping. There is in fact an internal rubber section on the piece it mounts to, so it doesn't have a gasket.

I can see that the other parts to the throttle body do have gaskets.


** note to self, fit permanent analogue boost gauge !!

[raptor95GTS]

......
** note to self, fit permanent analogue boost gauge !!

yeah absolutely have an independent gauge from the Boost Controller.