So I bought a 2wd Saph this week and it's running a bit sickly, before I send it off to be looked at was wondering if it's anything obvious. It starts first time cold and hot although it revs up and down abit, assuming that's just iscv or needs idle resetting etc but driving around it feels like it's struggling through the revs, and if you really put your foot done it coughs and stutters and misfires. Fuel pump also doesn't sound all that great so wondering if it's all related. Any advice is welcome. Thanks.

 

Could be a number of things mate. I'd start off with the easiest things.

Plugs (also check they are gapped)
Leads
Dizzy
Coil

I had a misfire last week, luckily it was my battery that died which i assume caused it to misfire/starve due to lack of fuel from the pump. Changed the battery and she's perfect again.

 

Could also be a faulty MAP sensor

 

Thanks guys got some bits to fit today so hopefully that will sort it or least cross a few possibles off the list.

 

If the fuel pump sounds bad, then this should be the place to start, it could be fuel starvation (so I would keep it off boost)

Re the hunting, you can try cleaning the valve, but I have done this and the problem still persists.

I tried an aftermarket valve, but this made the problem worse. You can't get hold of the OE valve, mine has always done it, so just got used to it, although it is annoying!

Also as it is new to you, I would advise you check the fuel pump and fans have been rewired.

Martin

 

Martin, I did have an aftermarket valve, same as you, made it much worse too so old one back on and cleaned. Didn't have much luck sorting it out myself so it's going away to be looked at. Fuel pump is on the list. I'm thinking new pump filter and wiring could sort it. Luckily all the rad and fans etc has been renewed fairly recently, even the metal pipe under the rad is new and shiney.
Need an ABs sensor too but can't find one for love nor money ( I've offered both too) What does everyone else do? Understanding Mot tester and live with the light on?

 

if idle is hunting check for any boost leaks. mine was doing the same thing a few weeks back turns out on the back of my t34 turbine housing it was leaking through a bolt. bit of lock tight sorted it right out

 

also another possible easy fix is check the gap on your spark plugs.
if the gap is too big on heavy acceleration the spark can get blown out

 

If it has closed loop fueling and the spark plug gap is less than .7mm is can also starts hunting at idle.

 

Bit of an update, new leads dizzy plugs etc and all the engine sensors replaced too, fuel pump and wiring checked out ok too. Runs sweet now, except for an annoying idle issue but pretty sure that's an air leak having read back some previous posts on idle probs. so that's tomorrow's job anyway...