running rough

[wotugonado]

Driving around today and the car felt quite rough and not as responsive as normal almost stalling from standing start, I checked the maf and air filter when I got back and both looked clean. I did drive round the last couple of short trips on fumes so im wondering if ive got some crap  in the system. Any ideas  on what it may be or  suggestions on something to put in the fuel to help clean it out ?

[Jay67]

Anyone local to try out a known good MAF?

[Davegtst]

Mine was running rough between 2k and 3k rpm the other day.  I tried new plugs, coil packs and MAF and still it ran badly.  I disconnected and reconnected the battery and it's all back to normal again.  Who knows what caused it but maybe it's worth a battery reset.

[wotugonado]

Anyone local to try out a known good MAF?

You reckon its maf related? It was my 1st thought to.

Mine was running rough between 2k and 3k rpm the other day.  I tried new plugs, coil packs and MAF and still it ran badly.  I disconnected and reconnected the battery and it's all back to normal again.  Who knows what caused it but maybe it's worth a battery reset.

Mad isnt it, ive cleaned the maf whilst it was out and will do the battery reset in the morning, thanks.
 I did also notice that the engine lid insulation was wet, my drive is on a slope so im wondering if water may have got into something that may have affected it ?

[Jay67]

Mad isnt it, ive cleaned the maf whilst it was out and will do the battery reset in the morning, thanks.
 I did also notice that the engine lid insulation was wet, my drive is on a slope so I'm wondering if water may have got into something that may have affected it ?

I had a similar thing when water got into the plugs and coil packs, worth a look if you found the insulation was wet.

[mrzwei]

Sounds electrical. It's not the obvious bit of the MAF that causes problems, it's deeper inside than you think. It's the thin very delicate wire that you need to spray, but you may well know that so apologies if you do   s:D s:D  

I'd check the plugs. I'm not sure if it's the roadster or not but I think one of the plug holes, either 1 or , can gather water. (You should be able to check that by just taking the engine cover off but you may as well pull the coil packs and plugs while you are there).

The only other water related thing I can think of is the crank position sensor where the connections can corrode because of water dripping on them.

Sorry to be vague but I've had so many cars that they start to merge into one   s:lol: :lol: s:lol:

Edit: Sorry Jay, you're quicker on the draw   s:lol: :lol: s:lol:

[wotugonado]

Thanks lads, plenty of things to look at in the morning.
Crank position sensor ill have a search ta

[Jay67]

Edit: Sorry Jay, you're quicker on the draw   s:lol: :lol: s:lol:

Don't tell everyone!   s:oops: :oops: s:oops:

[wotugonado]

Right so what started out as just a couple of hours this morning on the car, has led to pretty much all day   s:) s:)  
But has been productive, i stripped out the maf and the air filter cleaned both again, removed the battery to do the
reset and put back into place some wires that had come loose from there clips. Removed and checked the coil packs which
were all clean and dry.
Moved the charcoal canister to try to find the crank position sensor, which i couldnt see, so presume its on the underside.

Whilst i was there i partially wrapped the turbo pipe with heat wrap, not anything to do with this particular problem but
as i was there, why not!

Have to say that it has made an improvement on yesterday and the turbo felt punchier to, but the revs still fluctuated a bit and
whilst not feeling like it was going to stall anymore they still dipped below the usual 600 ish revs when you came to a halt.

Any ideas on a decent cleaner/additive to run through the system ?

And an exact location on the crank position sensor please.

[Davegtst]

You don't really get any crap in the fuel these days due to plastic fuel tanks.  You used to get it from rust particles in old steel tanks but as our tanks are plastic I doubt a fuel additive will cure your fault.  Can't harm to put one in though.  Have you checked to see if there are any fault codes stored?  Even if there aren't any it is worth clearing the codes.  I've known a few cars with no codes logged that run much better after clearing the memory.

[loadswine]

If its a turbo, that opens up a few more avenues to check. Have the inlet tract or exhaust developed any leaks? Leaking boost sensor pipes maybe? The boost reference pipe on the turbo is a prime candidate for a good look.

[wotugonado]

No codes and the battery was disconnected for a couple of hours so will have reset anything stored.Any additives that you can recommend?

Turbo is tte, and yes I think there is a problem with a potential crack on the precat pipe. Last year
I had a repair carried out where the precat flared end is bolted to the turbo. It had cracked all
around the edge of the flare. Potentially may of happened again.
Boost reference pipe? Will this be shown in the installation manual so i know what im looking for ?

[Davegtst]

Forgot to say my turbo also had a problem with it bogging down and no being very responsive.   It was caused by the exhaust manifold being slightly bowed and the manifold to turbo gasket having a slight leak.  After flattening off the manifold and some new gaskets it was like a totally different car.

[Anonymous]

The maf might need replacing. Cleaning doesn't always fit it. If it runs poor off of boost then I doubt its turbo.

[loadswine]

Yes, the boost ref pipe should be shown on the manual. It is the small diameter one that goes from the turbo outlet to the wastegate actuator. I have seen the odd one with small splits at the end. Its not a long pipe.

[wotugonado]

Thanks guys for all the advice, i pretty much worked through all the suggestions, except the crank sensor as i cant seem to see it,
i presume its underneath? so think i will need to get the car on ramps for that to gain access.

Few things i found along the way, which i put right were.....
The air filter box outlet thats right next to the maf, had been deformed by the jubilee clip, the edge had, the best way i can describe it as an v
shaped indent in it, which i dont think was then completely airtight. would this affect the maf sensor ?
I reshaped it as best i could, and put a plastic spacer over the rubber and between the jubilee clip to make a good contact on the outlet without
deforming it again.
I also checked the pipe loadswine mentioned above and found a loose jubilee clip on the actuator end, i did manage to tighten it up, but im not
happy with the clip so thats down to be replaced at some point.

Good news is that the car felt a lot better, bad news is i couldnt pinpoint exactly which thing it was that put it right   s:D s:D

[StuC]

Perhaps it was all the above that you tweaked. Just take the win dude.  s:-D :-D s:-D

[men3cac]

You would have been leaking air into the system after the MAF had measured it, throwing the fuelling out. If it is a standard air box it would be worth sourcing another. Sound like someone massively over tightened a clamp!

Glad you've fixed it

[wotugonado]

Yes it is standard air box, I will keep an eye out for one as theyre not expensive 2nd hand.
Well that would explain why it feels much better, thanks for the explanation

[loadswine]

Leak on the inlet and/ or boost leak could cause running issues, as well as a manifold leak. Always a good idea to keep an eye on things when you have a turbo. Glad its running better, that is good.  s:) s:)

[wotugonado]

Yep its much better, cheers for the heads up.  Its knowing where to start thats the problem. Turbo bit back though scratched my arm to pieces to get down the side of it. But taking the car out this evening, it was
worth it  s:D s:D