GrantyBoy

Hello. Got my Type R last weekend so I'm still getting used to it. I've been driving it pretty easy so far with only a handfull of full boost attacks throught the gears. No problem until tonight. After a few hours of town cruzing (showing off) I gave the car a few hard runs to show my mates what the new car can do. At the end of second gear she wasn't pulling as hard and it sounded like she was mis-firing, into third gear and it was worse. Aceeleration was their but not 'throw you in the back of the seat hard'. Did two runs like this in total and both where the same. Didn't want to push it again incase something was wrong with her. I don't have a knock sensor fitted yet as my scooby guy is away working offshore for three weeks from today.

It's a 98 Type R with Optimax and a bottle of Millers for every tank. Apexi exhaust. Car was sourced by newera so it should be of a high standard.

Only thing, ECU was reset one night ago. Could it be the car just relearing the boost/fuel maps?? First time it had really been booted hard since the reset.

Thakns in advance for the help guys.

GrantyBoy

help please!

leeps

Well IMHO i think it could still be knock and engine going into limp mode .....
Do you have a boost gauge? THat will tell u a lot! Other thing could be but
unlikely is that the coil pack or spark plugs have given in ... does the car
shudder a little bit when hitting full boost ??? Cant think of anything else

leeps

Bats-Wrx

iTrader: (1)

Is it turbo back or cat back exhaust???

GrantyBoy

The it's a full de-cat system. The car does sudder at the top end of second gear and into third on full boost.

Got a boost gauge and it's boosting fine. Just put more Optimax and Millers in to see if that will help. Now got around one and a half bottles of Millers in to up the octane.

This has only started happening since the ECU was reset.

Bats-Wrx

iTrader: (1)

What does it boost to???? and in what gear is it making that boost?

GrantyBoy

Bats-Wrx

Are you in aberdeen by any chance?

GrantyBoy

Bump for more ideas.

Put in more Optimax and another bottle of Millers so she know has around one and a half Millers in her.

Could it be the engine not getting enough fuel now she's been de-restricted, since its mainly in third or forth she hesitates. Do I need a FES boost valve then or a uprated fuel pump??

Another possibilty, car is over boosting so the ecu backs the car off. I've got a boost gauge and she apears to be boosting to 1.1 1.2 bar of boost in all gears. What could I do to sort this out if she is overboosting. Would I dawes device be the answer??

Or I could run the tank down of fuel then top again incase it was a bad batch of fuel and then reset the ECU again??

Suggestions welcomed

Bats-Wrx

iTrader: (1)

Edited due to me making a mistake.

iirc standard boost should be 0.9 bar on the car.

greasemonkey

Is the car a version 4 or a version 5 Grant?

Certainly wouldn't try hanging any boost control valves or other bits on it til you know exactly what it's doing. KnockLink is certainly an ASAP item.

Would really need to get in car to diagnose overboost, but when you say it's boosting to 1.1-1.2, can you see the boost gauge needle overshooting then dropping back to these levels, or does it seem pretty steady?

Unfortunately there's a stack of potential explanations, from det (which could be caused by degraded MAF sensor, insufficient fuel quality and more) to knackered/incorrect/badly gapped spark plugs, to faulty boost solenoid, to exhaust system inspired overboost and more.

Suggest keeping off the throttle til you have a KnockLink fitted, as if it is det, you could be prejudicing the life of the engine by continuing to boot it.

Also, before you reset the ECU, did you put it in read memory mode and see if there were any stored errors in it? What happens if you try reading its memory now?

GrantyBoy

The car is a 98 v4 Type R. She has a full de-cat Apexi system, but other than that she is standard.

The Boost gauge is very steady, shoots up to 1.1-1.2 the holds there no matter what gear she's in.

I thought they're couldn't be an easy answer. Russel from BHP Devolpments, respected scooby guy up here, did the ECU reset. The 'Check Engine' waring light flashed at one second intervals which Russel told me was a good thing showing there was no problems when we did the 10-15mph crawl to check. Unfortunatley, Russel has gone off shore and won't back back for another 2 weeks untill he can look at the car. He's got my Knocklink which he's going to fit and check the engine with det cans as well. Have gave the car the once over before he left and said she was mint. I'll drive her easy until he gets back. For keeping her off boost, would that mean stoping the boost gauge from going over the '0' mark as that's how I've been driving her since all this happened. Also going to keep the fuel at two bottles of miller per tank until this is sorted.

WUZ

iTrader: (14)

Grant came to see me B4 I went offshore to chat about the car and see about sorting out the KnockLink.

Plugged in the grren and black wires. Check for stored codes, none there. RESET ECU and got regulat 1/2 second "Check Engine" light so reset OK!

1. If the car has gone into limp mode due to det than boost is limited to actuator spring pressure (0.7 bar on VF24?) so if he is getting 1.1 bar then LIMP Mode can be ruled out.

2. Full decat fitted to standard ECU will allow the cat to run leaner on boost which does actually make the car feel faster in the same way as the car feels faster in cold wintry misty weather.

I suspect a faulty MAF (ECU doesn't detect it is knackered until it is fully dead so over a period of time the car adjust fuel thinking the MAF is OK but the fuel mixture is getting leaner and leaner) or possibly some form of fuel cut. I will put my spare on the car once I get home and see if this helps.

Grant, although it might be annoying you that the car is like this right now ,I assume you it is better than having it blow up on the bypass due to a dodgy MAF.

Anyone else have any ideas (more the merrier!)

Russell

GrantyBoy

I don't link it's a fuel problem as it's not a 'head against the windscreen' job when she hesitates.
Better to find a fautly MAF now then say 6 months down the line when it goes pop! I'll just drive her easy until your back, she should be ok for just communting to Dyce and back in rush hour traffic?? How long till your back onshore pal?

GrantyBoy

Just been reading up on faulty MAF sensors and a few people have commented on the car 'hunting' while idleing. My car does this, bounce from 500-1250ish, wihen she bounces up high while idleing the boost gauge goes up as well to the 30 mark then back down to the 60.

Is this another sign that it's most likely to be my MAF??

Bats-Wrx

iTrader: (1)

If a 93 maf is the same as a 98. I have one sitting you can try before russell gets back.

If you like.

GrantyBoy

I think they changed from v4 onwards, typical! I could be wrong on this though as I'm still learning about Scoobies (the hard way)

Does anyone know if I could use this 93 MAF in my 98?? Ta in advance!

Bats-Wrx

iTrader: (1)

I know they changed but i thought it was 99 onwards not 100% sure.

GrantyBoy

I've just read this on Scoobynet, did a search for faulty MAF

If you try to get one from Subaru it is exactly the same MAF as the one fitted to the UK MY99 and MY00 Turbo 2000's and don't let them tell you otherwise. Quite understandably they're not keen on supplying spares for imports, and so will probably give you the "that's only for uk models" line.

That was for a guy in a 99 STi RA. WIll this uk MAF fit my 98 v4 Type R, if so then its off to Subaru tomorrow to get one!

GrantyBoy

Just had a look at my MAF and this is the numbers on it

22680 AA271 A36-612 R71
8217 A

So which MAF do I need to replace it with??

krazy

I think the my99 (ie ver 5) was the 1st year of the thin film maf sensors that u can buy just the sensor (something 2 do with making the recall work cheaper in the us?).
I guess 4 u, u'd need the more previous one only available as a complete unit i think..

The_Judge

They are different unfortunately. MY99/00 part number is 22794AA010.

MAF is where my money would be, as you've already tried one of the tests below and posted...
There are a few things you can do to check the MAF, as well as symptoms to look out for...

1. With engine warm and idling, pop bonnet and disconnect MAF sensor. If engine stalls, MAF is probably OK. If there's no (or little) difference in idle, MAF is more than likely failing.

2. Reset ECU. If car drives more or less the same after the reset, MAF is probably OK. If car drives worse after the reset, MAF is more than likely failing.

3. Whilst in neutral, blip the throttle so the revs go to around 3000rpm. Then watch them as they fall. As they approach 1200rpm, they should slow down and settle gently at ~800rpm. If they fall at a constant speed and then nearly stall, or hunt rather than settle at 800rpm, it's another possible indication of a failing MAF.

4. An AFR of less than 0.75/0.8v at WOT, using standard lambda (not wideband!) and Autometer AFR gauge or equivalent.

5. Faster than usual performance - the leaner AFR, and ignition timing too advanced as a result, will make the car fly... until it starts to det (see below).

6. Excessive Knocklink activity - the lack of fuel in the AFR, and the over-advanced ignition timing will eventually lead to det. If you haven't got a Knocklink or det cans to be certain, a "bogged down" feeling in acceleration might be noticed.

Couple of other things from reading the above posts...

Are you absolutely certain there isn't a manual boost controller or bleed valve?

This statement is true, as long as the ECU has control of the wastegate actuator via the wastegate solenoid. If a manual boost controller is being used, the ECU has no control over boost, and the same boost levels will continue to be hit. The only thing the ECU can do is use negative knock correction. And it can only do that to a certain point. Beyond that the engine's in the lap of the Gods...