St205 Running Problem

[mxmad46]

Hi, i have just removed my engine and had it replaced by a local garage after it blew! new engine and turbo in now and started first time! however it idles absolutley fine but when you rev it a few times it stalls! for instance foot to floor rev up to 6k and dumps off fine, so you do it again and same thing! 3rd of forth time it starts dying then stalls! fire her up straight away and she's fine and idles all day just seems to be after a few revs! The things i and the garage have done so far to try an resolve issue:

1. checked all vacume pipes for blockage and correct fitting!

2. earth cable from negative Battery terminal to engine to eliminate possible earth failure!

3. replaced distributor and rotary cap!

4. engine diagnosis got error 31 and 54! (54 resolved as chargecooler was not filled enough) 31 relates to map sensor or turbo pressure sensor but i'm not sure that is the problem as it worked fine on the old engine!

i'm really struggling to get a answer and the garage seem clueless! i can't drive the car cause it just stalls so will have to stay there till either i can solve this or the garage suss it! its been two weeks now :-s i really need my car back!

please can someone help or suggest a possible fix?

[Leeky]

Yeah sounds like a metering issue to me.

I would check the Map sensor and also the lambda sensor - most likely candidate.

Does it pop/bang before it stalls?

Either not enough air, not enough spark or not enough fuel.

If its idling fine then that pretty much rules out the fuel system, as a blocked injector/rail/filter/pump i would expect to be noticable at idle.

If Map/Lambda is broken then i wouldnt be surprised if it wont rev.

Are you running the Dizzy from your new or old engine? If you have the one from the old engine i would swap it over to rule this one out.

[mxmad46]

Yeah it pops and bangs a bit! Before it stalls! I'm using the dizzy that came with the engine but put new dizzy cap and rotor arm on though! I used to run a bee*r rev limiter on my old st202 and if I set rev limit to say 2-3k rev it made a pretty similar sound!

[Phil01]

have you an after market dump valve as you say it dumps off fine,

[mxmad46]

Yeah got a baileys dump valve! Came with the car but I'm going to be changing that for a hks ssq3 very soon

[Phil01]

baileys are known for leaking air at idle. I would check that first mate.

They are a lovely sounding bov but prone to failure.

I fitted a HKS ssqv and its a totally different sound,

[mxmad46]

Yeah I heard about baileys problems but I had so far with mine! Think it was adjusted to open at a higher boost!

[mxmad46]

Right new map sensor came sat and fitted this morning! Same issue so defo not that! However if I disconnect the plug from the back of it it runs sweeeeeetttt! Anyone got any ideas???

[Leeky]

Probably the Lambda.....

[mxmad46]

Garage think that is highly unlikely as the emmitions are sweet as!

[Leeky]

Hummm in that case the only other thing i can think of (if you are certain there is no air leak) is that the timing is wrong.

If its a tooth out this could explain why it may idle fine but stall when you rev it......

[Phil01]

air leak from the faileys dump valve, as you say its ok but after a couple of revs at idle the valve aint reseating.

where are you what area as I have another bov for you to try

[Phil01]

one tooth out on the cams would not cause it to stall, it would make it lethargic, no power or will not rev

[mxmad46]

Ok update! Got it back from garage after giving up! If new map sensor is plugged in the car runs terrible and nearly moves before stalling! If I disconnect the map sensor it runs way better but still only gets to 3k revs then pops and bangs! But I have no power and no boost! So is defo not map sensor what about coil or summit? Also timing you say? Surely if that was out then I could not drive at all?

[Leeky]

I've seen a diesel do this before when it was one tooth out. This is why i suggested it if you arent 100% sure that the timing is correctly set.

Its unlikely as from what your written your idle appears to be normal, but its not impossible for it to be a tooth or two out that is causing it to stall.

I dont like Baileys dump valves either but i doubt its that which is causing the issue. As you had the same dump valve on your old engine and from what i can tell it worked fine on that. Plus i'd expect you to hear the air leak from a dump valve thats stuck open.

I've had a turbo to manifold pipe come off a car before and it didnt make the car stall.

[mxmad46]

I am pretty sure timing is fine as it was from a genuine breaker removed from a running st205!

Phil I live in Newcastle upon Tyne, where you from?

[mxmad46]

Engine was from a running car! So cant see it being the timing or problem would have also been obvious on the other car before breaking!

[mxmad46]

Ok problem is the fuel pump! New one is on the way! :-)

[mxmad46]

Hmm turned out not to be fuel pump as still nit working! Only starts by bypassing the relays in the diagnosis box! I checked relays and both are ok so I'm baffled!