ive got a 91 4x4 saff, t35 15psi, bayjoo stage 1 and the usual scorpion, pipercross, -31 etc. it, will sometimes misfire lightly under normal driving which you can rev through, but under load it will rev to between 4 and 4500rpm then lose all power, everytime you press the throttle it throws a massive flame out then cuts out, it will start up again straight away albeit turning over a fair bit more than usual. since the problem arose i have put on new plugs, motorsport leads, group a coil, rotor arm, dizzy cap, phase sensor, water temp sensor and rad sensor, checked the timing, checked the fuel pump is pulling enough voltage, but the problem is still here. i dont really want to spend any more money willy nilly on bits hoping it will cure it. HELP!!!! matt

 

ps: forgot to mention that when this happens the rev counter goes ape shit nd also i dont know if its related or a totally seperate problem but sometimes it feels very sligtly less powrful than normal and then dump valve sounds pants and whistly instead of the usual 'hgv air brake soundin' tsssh

 

hi mate, iv got a 4x4 saph and mine did somthing simular, when mine just came onto boost at around 3-4k rpm it poped and banged, blew flames out an missfired, as it did this the rev counter went through the roof.
i changed all possible sensors but still didnt cure,in the end it was dodgy connections on the 3 wire multiplugs on the engine loom. they are on the bulk head just above the rocker cover.
try puttin gresae in their first but i actually cut mine off and soldered wires together, no problems since
hope that helps

 

As already said mate if it spits and missfires under boost and the rev counter goes skyward and jumps around its an engine loom problem

had the exact same problem with my car and cut the multi plugs that run along the back of the rocker cover out and soldered up the wires, lasted about 16 months and problem came back,

new engine loom from Ryan and bobs ya aunties live in lover


Luciano

 

good old rs missfire

as mentioned get the multi plugs checked out on the bulkhead above rocker cover

also check the ignition module thats attached to the inner wing behind coolant bottle

 

the multiplug nearest to the battery connection is your duff one for the rev counter glitch

 

thanks guys, i'll definately be havin a look at those wires. If it does fix the problem i just hope its quite a while before something else breaks lol

 

by the way, does any1 have any idea of why my dump valve sounds pants sometimes and normal others? i would just assume that its had it but it does affect the performance a little. if it was a boost leak surely it would happen all the time not just every so often? i would run without it if i could but this car makes me a paranoid nervous wreck every time i drive it anyway so any protection 4 my snail is welcomed!

 

Multi plugs deffo check as for dump all depends on boost pressure and if you snap the throttle closed as it needs a lot of vac to activate properly

Paul

 

its running 15psi and it holds it nicely everytime, maybe it is just the actual valve itself. it was on the car when i bought it n it says severnvalley on top,i dunno much about it, how old it is or how good it is etc, i mite jus buy a new one and see what happens.

 

been havin the same problem with my car, a changed phase sensor, roter arm, dizzy cap, new leads, n plugs and it was stil the same read this thread yesterday n a greased the 3 plugs went out in today and it runs perfect now, thanks