Overfuelling?

dwayneb · Post by **dwayneb** » Thu Dec 24, 2009 8:36 am

my EJ has decided to go into full over fuelling mode. Used a full tank 60L? in less than 300km. Normally run about 11.5 to 12L/100k, now getting 5l/100.

Swapped computer over as I had a spare, still the same. What could be causing this, which other sensors should I be looking at, o2, MAF/MAP.

It was running perfectly before I had a bit of work done, (stereo and console work, and a bit of welding, but the battery was out, not too sure about the computer though). Got it back and drove good for a couple of days, then started missing at full throttle in 1st and 2nd. Then driving home yesterday, no good in any gear, and copious amounts of blue smoke. Checked fuel filter, little bit blocked, but not enough to inhibit flow.

Gannon · Post by **Gannon** » Thu Dec 24, 2009 9:35 am

So this is an EJ?? in a Brumby.

It will depend on what type of EJ whether it has a MAF or MAP sensor.

If it has a MAF, this could easily be the cause.

Tell us more about the motor (what model car it came from), what mods you have (type of air filter, exhaust ect)

Have you checked your codes or had the ECU scanned?

dwayneb · Post by **dwayneb** » Thu Dec 24, 2009 9:38 am

Haven't checked codes, don't have a check engine light, don't have access to a OBDT.

Motor is from a Liberty 89-90 model, air filter is from a Magna or Pajero, 2inch exhast.

AndrewT · Post by **AndrewT** » Thu Dec 24, 2009 10:38 am

For an EJ with bad fuel economy the first thing to check is always O2 sensor. They can go faulty enough to screw everything up without even throwing a check engine code. It's a common problem. Replacements can be had fairly cheaply from Ebay, the non genuine ones on there work fine from what I've heard.

dwayneb · Post by **dwayneb** » Thu Dec 24, 2009 12:18 pm

Thanks Andrew, will keep posting when I find out the problem, always happens at christmas time when most places shut down for holidays

thatsgoodsquishy · Post by **thatsgoodsquishy** » Thu Dec 24, 2009 8:22 pm

I had a similar thing happen on a skyline, turned out to be the fuel pressure reg. The diaphragm split letting fuel straight through into the manifold which made it run stupidly rich and hence run like shit and blow heaps of blue smoke. Haven't played with an n/a ej for ages so cant remember if they use the same style reg but might be worth a check.

Gannon · Post by **Gannon** » Fri Dec 25, 2009 4:48 am

thatsgoodsquishy wrote:turned out to be the fuel pressure reg. The diaphragm split letting fuel straight through into the manifold

That sounds like a probable cause. The EJ has a FPR that has a vac line that goes back to the manifold.

The o2 sensor wouldnt make 7l/100km difference, its only used for trimming the fuel mixture

steptoe · Post by **steptoe** » Fri Dec 25, 2009 10:10 am

if the fpr is stuffed in some cases diaphragm gone it allows fuel to end up in the vac line. Look fir that

dwayneb · Post by **dwayneb** » Mon Jan 04, 2010 1:13 pm

Some more information from my mechanic
-Computer came up with code for No.2 injector. Have now done ohms tests on all injectors. Suppose to be 11-12 Ohms. Number 2 is 37 Ohms. Also, all injectors are getting 9.56 to 9.78 except no 2 which is getting 11.86v. So far this is the only significant thing I have found. Vaccuum tested Fuel pressure reg and appears ok. Holds a Vaccuum. I am looking towards the No.2 injector problem.. Will get some more fuel and try with injector disconnected and see what difference I get. Getting lots of notes and scribble paper.
Haven't seen the Brumby for a week now, missing it big time

dwayneb · Post by **dwayneb** » Mon Feb 01, 2010 8:11 am

Got the Brumby back last weekend. The culprits were Computer, and a Fuel Injector. The computer was changed for my spare and I have had to borrow some injectors, (thanks Yarney).

All up $ 300.00 and a long list of parts required for the front suspension, that I have been letting go for too long.

Thanks to all who have posted.

Dwayne