[nemesis2187]

Hi gang, my brothers 94 vitara decided to run like a piece of crap while driving along beaudesert rd randomly out of the blue.
What it started doing was cutting out or struggling to run, u press the accelerator down and it would choke up then u release the pedal and the revs would go up for a moment then reduce to a very rough idle or die in the arse.
I checked for spark and all cylinders are getting a very healthy spark, then i checked if i was getting fuel, by undoing fuel filter at the back, and there seemed to be alot of pressure, i will get a fuel pressure tester to see where its at. Anyway i moved onto checking if there were any fault codes and low and behold it came up with air flow sensor (33) got a 2nd hand sensor from suzi spares put it on and.... nothing same problem but code 33 was no longer there, instead code 21 came up (TPS signal high or faulty) i dont want to keep throwing parts at it and not fixing the problem. I have a suspicion that the ecu is stuffed but i dont want to buy a second hand one for a couple hundred dollars and still not fix it.
Can anyone help by putting me in the right to direction or help with lending an ecu for 10 minutes. Any help is greatly appreciated

[nemesis2187]

I forgot to mention that it now will barely start, it cranks over and fire but most of the time wont idle and if it does idle its not for long

[Gwagensteve]

Failed fuel pressure regulator is my guess. The ecu is extremely robust and conservatively engineered. Yes, there will be lots of of pressure at the fuel filter- approximately 40psi.
The ecu doesn't have any means of monitoring fuel pressure. If it goes high the car will run very rough and stumble. Does it smell rich or black smoke?

Steve.

[nemesis2187]

no black smoke but i can smell fuel

[christover1]

My 93 LWB started doing similar on a recent trip.
Felt like I ran out of fuel.
But still did it after fuelling up, though it ran fine for ages before it happened again.
Runs fine for ages, then symptoms start again.
If I turn it off for a minute, and restart, 90% of the time it runs great again.
Seems to be at high fuel need situations, ie long hi speed or hilly off road stuff.
Though could be heat related.
I suspect a fuel related issue, but guess I will be throwing parts at it for a while

[christover1]

Cracked the nut on the fuel rail, and it was under very little pressure.
(when changing the engine I did this and it was a huge spray)
I suspect it is fuel pump related.
Is probably 22 years old.
Tank has had a few wacks, too.
Fuel filter not been on long, don't seem blocked,
as fuel does flow out the rail when ignition is on.

May be time for a long range tank and new pump

Will keep checking stuff before spending any cash.

[christover1]

A bit of ebaying discovers efi pumps are so cheap, it will get one anyway.
Along with a filter and a tank clean/check.
Would feel safer outback.
Anything else will be easier to get to if it don't solve the issue.
Need to get the heavy work done before next hospital visit.

[Gwagensteve]

Check or replace your fuel pressure regulator. I'd do this first.

Experience is showing they are getting to an age where they are failing.

Steve.

[christover1]

I will do that, too.
Is that on front of rail?

[Gwagensteve]

I don't recall- I think it's on the back of the rail on a G16B.

[christover1]

Unsure why I asked, now, as it is pretty obvious after a look

[christover1]

The regulators are a bit dearer and harder to get, so I may have to visit a wreckers.
I sucked on the vac hose, was a bit stuck, but came good.
Could definitely be an issue. Could explain the intermittent nature.

[christover1]

Amazon have new ones listed.
Cost a bit more, but were listed to suit.
Ebay only had carby or universal types listed (or ricer boy types), which looked like maybe fit.

[christover1]

Pulled tank out today to fit the fuel pump.
Once the screws were removed, the whole unit sprung up 20mm.
Fuel pump must have been holding the tank dents out
No wonder it was struggling.
Pick up was hard against the bottom.
Think I will start with a new tank, and add a guard

[christover1]

Amazon regulator arrived today, after a hiccup with first delivery attempt (never got out of USA and was returned by carrier?)
New tank fitted, has been driving great since.
It is still a bit rough at idle, so new vac hoses with new reg should be sweet.