Weird running Problem
Turbo Mini Forums

Well i took the mini out last night for maybe 25 mins, after i gave it a little bit of stick i was just on the way home and it started to miss fire / back fire even when not under load? So i put it in the garage cause i had to go out, but went out there a minute ago and started it up and now it runs fine?

last night it would rev to 4000 rpm (not in gear) then back fire?

Now i have a few theories?

1) Spark plug breaking down under heat?

2) Ht lead breaking down under heat?

3) Coil pack breaking down under heat?

4) Map sensor playing up under heat?

Before I start replacing stuff any ideas?

thanks for your help!

stefan

"Cars are a lifetime of pain"

I presume its on megajolt?

Check that the plug is ok into the megajolt unit, could have reverted to edis limp home mode?

No its on omex, not megajolt, ITs fine when the engine isn't warm.

"Cars are a lifetime of pain"

Boost leak?

whats it like when u floor it from slow revs?

1/4 Mile 14.3secs 96Mph Terminal 10psi of boost.


Fibreglass Parts? - http://www.tdkracing.co.uk/
Split Rims? - http://www.force-racing.co.uk/

not a boost leak otherwise it would do it when it was cold or warm?

Mike, if its from cold and i floor it, (not to much but as a normally do) it reacts as per usual, then once warm and you floor it, it will cough and splutter like the timing is miles out and then backfire......but only when its warm!

strange!

"Cars are a lifetime of pain"

Hmm. Does it idle funny, wonder if the heat on the manifold is causing an air leak? Try spraying wd40 on the joints.

1/4 Mile 14.3secs 96Mph Terminal 10psi of boost.


Fibreglass Parts? - http://www.tdkracing.co.uk/
Split Rims? - http://www.force-racing.co.uk/

Have you re-checked the valve clearances ?.

is it backfiring out the carb or the exhaust???

Choke seals??

https://www.facebook.com/pages/Fusion-Fabri..._homepage_panel

www.fusionfabs.co.uk



1/4mile in 13.2sec @ 111 terminal on 15psi

valve clearence, choke seals etc would all be out because they would happen all the time surely, ITs backfiring out the exhaust. but like i said only when its warm? keep the ideas coming though? It happend after a run, so it sounds like its something thats breaking down.......

hmmmm......

"Cars are a lifetime of pain"

I think all you can do now is eliminate each component one at a time, try a new coil pack, leads etc

It could be heeps of stuf: Valve clerence, sticking valve, choke seals leaking when hot, gasket leak hot, heat soak into flot chamber etc

Make sure the two middle exhaust valves arent sticking open when hot. Ive had this happen a couple of times. The can guides swell up after a while and need reaming out.

Paul

I seriously doubt it!

i had something abit like this with my N/a i changed the carb on it and it was way to rich it was okay at low revs but if i booted it it would backfire big time out of the exhaust. may not have anything to do with yours but may help?
p

Drives
-Ford S-max Mk2 Ecoboost
-Rover 100 VVC #2 - track project

Searching is all you need on TurboMinis

are you using the typical ford coil pack?? if it could be breaking down as ford coil packs are SHITE!!!

yes i thought coil pack, its a rover one, so there probably just as bad!!! I'm going to try that first? then plugs and go down that route!

"Cars are a lifetime of pain"

id recomend puttin a msd coil pack on it!

you know the american company who do all the ignition bits for yanks and imports??

thats if its the coil pack that is!!

if all the ignition side checks out and the above is ruled out etc...... the problem will lie with the mixture too lean under boost.

check pauls answer out if it has manganize guides fitted!

fair enough it could be fueling but i doubt it would be under boost as when hes sitting there free revving it isnt making boost becuase its not under load!!


im placing my money on ignition!!

I've seen the msd stuff, Which one in perticular, I've ordered stuff from summit before so i know they do them. Maybe i'll speak to the guys at overhoaring! hahaha

cheers chaps.

"Cars are a lifetime of pain"

if its poping out the exhaust after a hard squirt and this continues for a few seconds on overrun i'd second the sticking valves.

if somthing has caused the micture to go lean this can cause sticking vaves due to the extra heat.

when it does it listen for an increase in tappet noise

nope its deffinately not sticking valves, It can't be, it gets worse the longer you leave it, it does it a little say after 5 mins then starts to gradually get worse so you can't really even drive it! Its something breaking down,

i'm going for coil pack, if it was a spark plug it would still rev past it but would stutter past it! Its across all 4 cylinders....

"Cars are a lifetime of pain"

is this the one DD was going on about?

http://store.summitracing.com/partdetail.a...15&autoview=sku

Is it only the ford style plug, rubbish, if it is i have to change mine over from rover to ford?

"Cars are a lifetime of pain"