jonof

So,
we've put the scoob back together after doing the following to the engine:

(2.0 turbo WRX STI Prodrive 2002 car)

Removed TMIC
Plumbed in FMIC with new forge dump etc
Replaced red inlet manifold with bespoke (cosworth type) racing manifold
Moved induction kit to low down pickup...sensor as close to turbo inlet pipes.
Replaced radiator with racing aluminium

She starts, but runs poo! Very lumpy, hardly any throttle response and smells really rich!

'HELP', she's supposed to be going upto RMC either tomorrow or Sat for full remap on Wed, so any advice or comments!!
Ta

Boost luver

iTrader: (3)

Have you tried resetting the ecu if you have had sensors unplugged? Double check for any loose pipes/vac pipes? No leaky injectors, are the inlet gaskets sealed properly..

IainMilford

iTrader: (15)

Sounds like it needs a map, can you trailer it to RCM or get a mapper to come out?

jonof

Thanks for your reply!!
How do we reset the ECU? The main battery was removed during the work, but ignition was turned on to test new gauges,
I hope the inlet gaskets are sealed

jonof

Yep, it's booked in for full remap on Wed at RCM...yep going on trailer!

Will the 'bulky' stuff that we've done **** up the existing map that much?

craigo

iTrader: (1)

You have called RCM for their opinion ?

JTinnovations

iTrader: (2)

Have you changed the induction pipework diameter, especially around the MAF (assuming you're still MAF based) and/or relocated the MAF? If so, you may well have messed up the MAF scaling and should not drive the car until it is mapped.

jonof

Well, not specifically, as they are very busy, and as the car's booked in next week, didn't want to waste their diagnostics!

craigo

iTrader: (1)

Im quite sure they would be happy to help you out. Being a customer and all...

jonof

Well, the MAF has moved slightly, and is different to the one before, in that it's now closer to the turbo inlet pipework. That turbo inlet pipework has changed to a racing silicone pipe. I'm not sure if diameters have changed tho'
Cheers for your comment

jonof

I'm sure they would!! And maybe they'll have to sort it when I take it there!!
Thanks for your comment!!

JTinnovations

iTrader: (2)

It's a different MAF (as in different make/model as opposed to simply replaced)? In that case there, probably, is your answer as the scaling will be wrong. That means the air flow as calculated by the ECU will not match the actuality and the fuelling will be screwed.

Please do not drive the car. When less experienced, I replaced the stock MAF tube for an 80mm one, and had poor idling and lack of power - drove it very carefully 80 miles off boost to the mapper, and destroyed my engine in the process.

jonof

It's the same internals (the MAF that is), but the pipework has changed!!
I've no need to drive it, but wanted to run it (tickover) to test the radiator ie water connections, levels, leaks etc! Is that very bad!!??!!

JTinnovations

iTrader: (2)

I'll be honest and say I don't know for sure if it's "very bad". If running very rich, you could suffer bore wash, where neat fuel strips the oil film off the bores.

If the MAF tube diameter has not change that much, and you just let it idle for a few mins to check for leaks, then it should be OK. Smell the oil afterwards, maybe? If it smells strongly of fuel, then change it, as it means fuel as run down the bores in to the oil.

This has to be your decision, and I do suggest you consult RCM or whoever and do not do anything risky based on anything I've said

toneh

iTrader: (1)

Id double check the injectors and fuel pipes , if there's a heavy smell of fuel under the bonnet as for running rich and bore wash I keep hearing this , in the old days (classics ) the ecu wasnt quite as good as bug onwards
Now with 01 on you have got to do serious changes to make the car undrivable (or not be able to get it on a trailer )
As regards maf scale you would have to be very drastic to make the car not run because the ecu can correct closed loop fueling up to a point
Now from experience and trying 3 totally different induction set ups none of them put the maf a/f correction ridiculously out of scale
Now I'm not saying that's ok at all it's not , but like I say the ecu is not stupid and will try and correct A/f issues
Here's an example , I was logging with l/v and the ecu was adding fuel at idle car was driving reasonable but not right , turns out inlet pipe had a big split half way round , now if the ecu can try and compensate for that issue , maf location and pipe diameter will be no problem
Now that said I stress maf or injectors that are not scaled are not right and wouldn't advise using a vehicle like that
All I'm saying I doubt very much your car is running as bad ad your describing due to unscaled maf
Your issue will be elsewhere

Shmerman

iTrader: (14)

Possibly sucking in unmetered air.

I would double check all your boost pipes front mount pipes for any leaks. check that any spare take offs
On the inlet manifold are blocked off and that it is correctly seated/sealed. I would the check the dump valve is sealing our remove and block off.

toneh

iTrader: (1)

Would agree with that , far more likely than maf scale issue

jonof

OK,
so a bit of an update!
Taking off the pipe the air filter side of the MAF, and then blocking the hard pipe that houses the MAF with my hand, and she runs smooth, albeit slightly higher revs.
Plugging in the diagnostic meter, it comes up with 'gone into limp mode', so it does look like the set up of the MAF does it not!?
I'm not going to run it any more until the remap.....I checked the 'smell' of the brand new racing engine oil, and that doesn't smell of petrol at all, but i will drop it out (even though i only put it in yesterday)
cheers for the replies!!

toneh

iTrader: (1)

It can throw a cel just by unplugging the maf , and all I know from experience is out of three massively different inlets none made it run how you describe , have you driven it to let the ecu re learn , or just let it idle for a couple of minits
Btw if your having it mapped why don't you just go mafless , way better and less hassle !

JTinnovations

iTrader: (2)

Turbo intake pipe changes, fine; induction kit fine: the ECU will cope.

Change the diameter of the MAF tube, or the airflow around the MAF, and it is most likely to have an effect that the ecu cannot "learn". The MAF and its housing are a precision sensor designed to accurately measure air, and it will adjust all sorts of other things based on what air it "knows" is flowing in to the engine. Mess up that reading and you're doomed.

I am, of course, speculating, as we don't know exactly what the OP has change in relation to the MAF. As I said, I changed to an 80mm MAF tube, had abysmal idle and bad running...and destroyed an engine on the way to the mapper.

YMMV.

toneh

iTrader: (1)

I agree mate the ecu can't learn to adjust maf but it tries to adjust to the information it's given , maybe I've not described what I mean properly , by learn I mean it knows to try and correct fuel to keep correct afrs , it's not fixed and will try and sort things out
I've gone through standard air box , cheapie s shaped induction and a straight silicone 76mm inlet and none have put the afrs out of the set map range , if I remember right my +and - was 14.99 % , admitted you don't want to be more than + - 5 % (and 0 is perfect ) but it shows that none of the inlets pushed outside of the ecu correction limits , that's why I'm finding it hard to see what the op has done to put the fuel correction out of limits

Shmerman

iTrader: (14)

So your stopping air entering the engine via the inlet tract? But it now runs smoother?

It must be drawing air in from somewhere for it to continue to run.

JTinnovations

iTrader: (2)

And with all those variations, you dont appear to have changed the MAF tube So the ECU always had an accurate measure of how much air was entering the engine.

I think the only way to be sure my theory has at least some merit for the OP to show a picture of the new MAF setup

toneh

iTrader: (1)

Er don't understand mate , I'm assuming you mean my air inlet tube where the afm sits , if so I don't know how a 76 mm silicone inlet is in any way shape or form the same as standard , I had my afm mounted on a steel joint piece and the silicone tube reduced down to my turbo , so no my afm was getting nothing like the same airflow , yet as I said still never. Exceeded the map correction value of 14.99%
Also I doubt the op has gone larger than 76mm but if he has I'd have to ask the question why ?

JTinnovations

iTrader: (2)

I think the newage MAF tube is 73mm...so going to 76mm may not have made much difference. Mine was 80mm, so obviously more significant.

But we still don't know what the OP has done so this could all be b*ll*cks

toneh

iTrader: (1)

Lol very true could well be , 73 , 76 , 80 , yes I agree but even considering the size difference , I can't see how his car is running that poor , by the sounds of it undrivable , if your car was like the ops car sounds would you have driven it or been able to drive it 80 miles on boost or of ?
It sounds to extreme to me , or are some folks idea of running poo a hell of a lot different to others
One thing is for sure rcm will sort it
And to the op go mafless , save your self the hassle , you can even run a drain pipe if you fancy ( still need afm but only for iat)

jayallen

iTrader: (31)

A silly question but....You do have the maf/housing the correct way round?

toneh

iTrader: (1)

hi mate
I guess you saw the thread about the induction kit yesterday and the out come of the problem , can't rule anything out on here

jayallen

iTrader: (31)

No i didnt fella, what was it all about?

toneh

iTrader: (1)

Take a look ,,, Induction kit help by daz
Now I'm not making fun or taking the mick about anything or anyone on here just pointing out how silly things can catch folk out me included