Engine Stalling and loosing Power.

[GavDaniels]

Hey Guys,

I have had an ongoing issue with my Legnum for quite some time which I need to fix.

The initial problem back before easter this year was that the car would start and idle, but not really accellerate. Once it got to about 2500 RPM it would die down and either stall or almost stall.

The car went in for it's 100,000km service at Tech Sport just as this started happening. They diagnosed the issue as being the MAF sensor and replaced it from their wreck car.

Car ran fine for about 2000km then started exhibiting the same issues. I found that the airbox was broken and could have been allowing dirt into the MAF, so I glued the break back together and replaced the air filter with a HKS from Carsten (Gly) and put in another second hand MAF sensor I got from NZ.
Car ran fine for about another 1500 - 2000km then started exhibiting the same issues again.

From advise from CVR4 people I pulled the Idle Speed motor out and cleaned it.

Car ran fine for a short period of time and then started playing up again.

All the times it has played up (until now) is when I have been out and about then it seems to settle down again for a short time. So when I have started trying to chase the issue it has refused to play up.

But just now it does not want to come good, so I am looking for suggestions on what else I should be looking at.

Regards

Gavin

 

[Guest]

sent you a pm with more possibility's.

 

[steveP]

maybe its fuel related. fliter or pump could be playing up.

 

[GavDaniels]

Hey Guys,

I havent checked the Pump, but have replaced the fuel filter.

Doesn't appear to matter if the car is hot or cold. It has done it after an hour of driving, then at other times the car will have been sitting for several hours and wont run when started.

The only thing that is constant is that if I disconnect the MAF sensor, it will run. It then just chews through the fuel and the auto wont shift properly for first thru third gear in this state. Just really clunks into gear unless I run it up to 4000RPM.

Problem basically just appeared early this year. Car had done 7000km since last service and I was just prepairing for 100,000km service.

Regards

Gavin

 

[steveP]

its as if theres a fualt with the ECU and the air/fuel ratio goes crazy. possible replace the ecu or perform some diagnostics on it.

 

[GavDaniels]

Hey Guys,

I have a new ECU which I am going to try later in the week.

Fr those who have more experience with Evoscan, here are some log files from my car while it is doing this.

http://www.gavdaniels.com/Legnum/SavedDataLogs.zip

Maybe somebody might see something i am missing.

Regards

Gavin

 

[Guest]

i had aproblem with my car that had the exact same symptoms, my
BOV wasn't fitted correctly this may not be the problem but its usually the last place you'd check

 

[naughtika]

usually I'd suggest air leak somewhere.. Im guessing your car's auto.. if it is, have you recently changed oil?

 

[GavDaniels]

Hey Christian,

Auto was serviced at 90,000km at Tech Sport. Had done 7000km when it started playing up.

Have checked for any air leaks, all turbo piping and alike seems fine. I cant hear any vacuum leaks.

I had Jeff at Tech Sport check the BOV when it was in there for the 100,000km service. He stated that there was no issue with it.

Regards

Gavin

 

[eddyvr4]

if youve changed the MAF twice and this has fixed it for around 1500 - 2000kms each time youve got to be close - maybe a MAF sensor connection problem? something your touching when your changing the MAF sensor...You really need to look for any error codes logged. have you checked clubvr4.com?

Good luck..

 

[Mel-D]

Gav as Eddy said when you move the Maf you could be moving something else. My car was losing power and had burnt out a spark plug.Over time we tried different things that all seemed to solve the problem for awhile.
The problem was the hose from the intercooler which runs under the Airbox had been loose and eventually came off. Then the car hardly ran without stalling Pete was checking the spark plugs and dicided to clean the filter and it was at then the car was worse ,so he took the whole Airbox off and found the hose had come right off. When he reconected it she ran perfectly and now she been great for three months.
List of things we did to find prob.
Got mechanic to check for leaks.
Got injectors cleaned.
Changed coils.
Swapped Mafs.
then he cleaned the airbox and car got worse so that's when he took it off and found prob he thinks pushing down on the airbox fully dislodged the hose thet was the prob.

 

[naughtika]

was gonna suggest this..

also with the MAF sensor connector.. its got that orange rubber seal.. see if its there.. if not.. probably why it keeps stuffing up..

but my car's no where near so I can't verify if it has one or not..

 

[GavDaniels]

Hey Guys,

I have successfully made the situation worse.

I started dismantling the airbox and airflow side of the engine bay looking for damaged wiring and alike, also air leaks or vacuum leaks. Couldnt find anything of issue.

Car would start but not run unless it had some rev's.

I moved it to the lawn where it would be easier to work on it. This was Wednesday before Xmas.

Got back to it today. Now she wont start at all. Cranks over but wont fire.

Checked IFS, appears fine. Tried jumpering it out but no go.

Any ideas?

Regards

Gavin

 

[bradc]

Pull everything apart again to check that you haven't unplugged something?

Or check that the spark plugs are sparking when you crank it over?

 

[GavDaniels]

Well,

Another few hours, and just poking around at things and the problem became evident.

At some stage in the past, a relay in the ASC system in the engine bay had come off it's mounting and was hanging down.

It turns out that this is the fuel pump relay.

I only found this because I was going over everything I had touched the other night, and I remembered that I had picked this up from hanging on it's wiring and put it back on the mounting.

Upon opening, the relay was severly caked with muck and beginning to rust. A quick clean with some WD40 and checked the coil found that the relay was still operational.

Reinstalled and the car started up first time.

Could somebody with ASA running (only have CAPS installed on the service laptop) please see if they can find me a part number for it. CAPS returns a NO DATA for the fuel pump relay.

Thanks for all the advise

Regards

Gavin

 

[Guest]

Sounds like you may be getting there Gavin. Part number is MR212219

 

[GavDaniels]

Hey Guys,

Peter - Thanks for the part number, but again Mitsubishi Aus have proven to be useless and cant even give me a price on the part.

I have on one the way from DVR up in NSW, but have also managed to get one from Jeff at TechSport today, so the car is operational again.

I do hope that this will resolve the ongoing issue with the car, and has left me with a few spares, one of which is a 7202 ECU which I discovered I didnt need to buy since my 06/97 Legnum has one factory fitted.

Looking at the fuel pump wiring diagram the pump must have a high flow and low flow modes. In 1 mode the power to the pump is run through a resistor located next to the relay. In the high flow mode it receives straight 12v.
From driving it today with the rusty relay installed, the relay must change from low flow to high flow at about 3500rpm, as there was a noticable hesitation which is now not there with the new relay installed.

Thanks to all who provided input and assistance.

Regards

Gavin

 

[gorgath]

Well, I am having this problem now after dismantling my airbox last night to get it a clean. And no, I didn't touch or cleaned the MAF itself, I just took off the pipe.

Now, the engine is on a brink of stalling everytime I stop and it is like there is a massive lag everytime I stepped on the gas. I will have to double check everything again to see what is the culpit. Bloody cars!!! hehehe

 

[Guest]

it's not an oil breather line? or wiring plug not connected

 

[bradc]

I'd guess the same, you either haven't put everything back in, or accidently disconnected something! Or your airbox may not be airtight? I doub that would matter much though as it is before the maf.