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Outback Jack

4.0 OHC - Fault finding hesitation/missing on acceleration.

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Hey Guys :)

Outback Jack here, I'm going to start this thread on trouble shooting rough running on the 4.0L SOHC motor as found in E series and the X series, like my XG ute.

 

There's a lot of stuff on the net but not a lot of solutions, so first we will look at my ute, and then use the thread to help others diagnose their problems.

 

OK, first up, some details on the ute.

Type of vehicle:

 

1996 XG ute- Outback. Manual 5spd.

 

Problem:

Ute has stuttering/hesitation/missing under load/accelerating from stop.

Usually in lower gears.

Has stuttered/missed once at speed while overtaking on highway.

Symptom lasts 3-4 seconds then clears.

Motor seems a little down on power in general when pushing accelerator at cruising speed/accelerating.

 

 

Work so far:

 

I have run a code reader on ute and has NO fault codes with Key.On.Engine.Off. test or Key.On.Engine.Running. test.

All clear.

So it's nothing the ECU monitors.

 

Condition of motor and bolt ons:

 

Fuel pump- Good.

Fuel Pressure Regulator-New

Distributor- Bosch , 7yrs from new.

Fuel Injectors- replaced last year.

Thermostat- replaced last year.

Fuel filter-replaced last year.

 

Motor has a bit of an oil leak on coil side of motor, not major. Coolant levels stay constant, Oil is nice and clean.

Have a ticking lifter that has been the same for years and ute ran fine with this in the past, or at least no hesitation.

 

Checked all leads with a timing light and all set off the light fine.

Plugs are due for a replace, will be first thing I do today after gapping properly.

 

I have a new set of Bosch leads, NGK plugs and a New coil ready to throw at it but might wait until I have a new dizzy cap and rotor here, as getting to coil and dizzy is a mission on the XG, so might as well do it all at once.

I also have a new fuel filter just in case.

 

That's about as much info as I have so hopefully with that and past experience from others here we can narrow it down, and I hope this will provide info for others with the same sort of problems in the future as these models get older.

 

Cheers!

Outback Jack.

 

 

 

 

 

 

 

 

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Just a heads up for XG ute owners.
May fit other E series too.
Super cheap Autos has Bosch rotor caps and rotor buttons cheap at the moment.

Bosch Rotor Cap suit XG
Part no. GB862C
$4.99
Bosch Rotor Button suit XG
Part no. GB865C
$4.99
Usually a lot more expensive to buy these.
:)

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OK, today I'm doing the fuel filter and changing the plugs.

Will then take her for a drive and see if that makes any difference.

 

It's got to be fuel or spark that's causing the hesitation/missing.

I don't think it's the plugs but they are due for a change.

 

I'm leaning more towards fuel filter, but could be breaking down coil or lead, dizzy cap or rotor fault.... and at the worst the tfi or a fault in the electrics, will check the injectors as well if needed.

 

Start with the simple-cheaper things first.

 

Will be back with results after I've taken her for a run.

 

 

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i'm always sus on leads or coils for misses etc..  usually due to being well overdue for replacement

Hey dean,

Yeah the leads, coil and dizzy cap/rotor were next on the list.

Waiting on Bosch Dizzy cap and rotor to get here so I can do it all at the same time.

 

OK, well today I started by pulling out a proflow fuel filter, has a sintered metal filter inside.

4177eb4262abefaf25320b9b5a140493.jpg

She was a bit dirty inside and I had been wanting to go back to a Ryco set up.

Fuel filters on these Ute's are usually bolt up type but people always round off the nuts making it a bastard to fix.

I have cut the hardlines back a couple inches each side so I can fit a barbed Z200 ryco filter in.

Took a bit of messing around but now even sits in stock fuel filter holder.

be211c3862d01dd9af7dfa742f2c1409.jpg

While I was under there I noticed the vapour line that goes to the carbon cannister was split at both ends where it went over the connectors, so that was replaced as well. That would not affect the running of the ute, just a do it while your there job.

 

I had a set of Bosch plugs in the ute, which were overdue for a change.

4c2157f9487560d165d16a3604e1d1b9.jpg

As you can see they have been running a bit rich. You can see it a bit better in this pic....

b60056635e6b2b891fe26c69067d6761.jpg

I think what has happened is the fuel filter was semi blocked, causing a lean condition at the O2 sensor, which the ECU then Richens up the mixture to compensate. Hence the darkish plugs.

Plugs were replaced with standard NGK BRE527Y-11

 

I have taken the ute for a 110km drive and it is more responsive and the hesitation/missing seems to have stopped on take off

Happy days.

 

I will continue on with this thread as I want to replace the dizzy cap, rotor, leads and maybe the coil.

 

We will see how long the fix lasts, but that fuel starvation and rich plugs is something to watch for when fault finding.

 

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2 hours ago, Outback Jack said:

I have cut the hardlines back a couple inches each side so I can fit a barbed Z200 ryco filter in.

Took a bit of messing around but now even sits in stock fuel filter holder.

be211c3862d01dd9af7dfa742f2c1409.jpg

 

 

that old crusty hose clamp doesn't look EFI pressure rated .. i'd be getting more like the others... 60psi ? unregulated pressure on that filter.. really wouldn't trust that clamp to be honest. 

 

otherwise, sounds good so far

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that old crusty hose clamp doesn't look EFI pressure rated .. i'd be getting more like the others... 60psi ? unregulated pressure on that filter.. really wouldn't trust that clamp to be honest. 
 
otherwise, sounds good so far
EFI pressure rated hose clamps...
First I've heard of that.
Maybe on higher pressure systems.

They make efi hose clamps with an extended tang to prevent hose damage but that's all I've seen, other than that they are just hose clamps.

The fuel line only holds like 30-32psi, roughly 350kpa, the rest is bypassed by the fuel regulator.
Those clamps will do the job just fine, have been using them under the ute for years with no problems.


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9 minutes ago, Outback Jack said:

EFI pressure rated hose clamps...
First I've heard of that.

the engineer i consulted on My lexus v8 into XE wanted them,  because it was a carby prior.. 

i went to enzed and asked for them and got " efi hose clamps with an extended tang to prevent hose damage" that were supposed the best available.. 

 

i'm just bringing it to your attention in case you hadn't considered it. i'm fine with it if you are.  

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All good dean, the hose clamp that looks 'crusty' is actually off the efi system.
It does look a bit dodgy, must be the pic angle, but I assure you it's fine mate.

It was the other ones I was worried about, so I put 2 on each hard-line...haha.

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G'day Jack, I had that miss in xh van at 100 k on highway.. happened 2 or 3 times over period of time.. just a half second or so, very disconcerting. Usually the other time it happens is sitting at lights idling, total miss then runs ok , miss again 20- 30 secs later. It was real bad a while back and I read on another Ford forum about faults occurring in ecu. Pulled it out for look see, not that I know what I'm looking at, but decided to get another and jagged one on ebay. It went in when I took it to my bro-in-law for brakes overhaul and tune up.   Big difference.. no more missing under cruise or load, but lately the miss at idle has returned.. annoying ain't it... ?

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G'day Jack, I had that miss in xh van at 100 k on highway.. happened 2 or 3 times over period of time.. just a half second or so, very disconcerting. Usually the other time it happens is sitting at lights idling, total miss then runs ok , miss again 20- 30 secs later. It was real bad a while back and I read on another Ford forum about faults occurring in ecu. Pulled it out for look see, not that I know what I'm looking at, but decided to get another and jagged one on ebay. It went in when I took it to my bro-in-law for brakes overhaul and tune up.   Big difference.. no more missing under cruise or load, but lately the miss at idle has returned.. annoying ain't it... ?

Hey vanJack default_smile.png ,

I have replaced an ECU in the past, about 7 years ago.

The first sign usually something is wrong is the aircon doesn't work properly and Erratic idle.

The most common fault on the ECU's is a blown Low idle circuit internally.

Which is connected to part of the aircon system.

 

Aircon if faulty MUST be repaired before ANY other testing for faults is done.

 

This problem (code 67) needs to be rectified before you can get the ECU to self test in running mode.

 

The low idle circuit is linked to a lot of other systems on the ECU.

 

Faulty ECU low idle circuit can be misdiagnosed as a faulty thermistor on the air conditioner.

This controls the aircon temperature.

Plugging in a new ECU with a good low idle circuit will let the thermistor function again.

Hope that explains what your problem maybe was.

 

A lot of things can cause idle problems on XG's, intake vacuum leak, idle speed controller, dud spark plug or lead.

I try and go through the simpler, less expensive stuff first and go from there.

 

Jack.

 

 

 

 

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Hmmmmm…. very interesting, seeing as that was exactly how it played out. A/C shit itself, not sure how now, cant remember, hasn't worked since not long after I got it.. out of gas, I think.. and friggin major idle issues.. much hassling with idle circuit control no joy till ecu replaced, then sweet. Don't know what the go is with fault codes cause bro-in-law is actually old school Ford mechanic, and tragic, has all the code gear, always get van back with the little spanner gone.. although its back again now, next service I guess..                                                                                                                                               It's actually ex NSW police service, Enfield according to Owners Manual.. interesting little points of interest around it..                                                                                                  Can old ecu's be repaired, I fancy it went harder with the cop one in, but maybe just my imagination.. and going by what you said I should sort A/c as well..                                     These old girls just keep on demanding..

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Interesting read on the A/C.

 

Mine stopped working in the XG just before summer. Car got real hot and the AC hasnt worked since. Still idles and drives fine though.

 

I had a look on the weekend and the AC relay is switching but the clutch on the compressor doesnt cut in at all. I checked the over temp cut out and that is in tact as is the wiring to it. I wasnt able to find the 12v to the compressor yet and gave up. Something ill follow up when i can be stuffed.

 

The whole engine will be pulled soon with the windsor going in.

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Hey Guys,
The code that shows you aircon is ON or in Drive is Code 67 and will appear during a Key ON /Engine OFF test.
Workshop manual says this must be corrected before continuing.
The vehicle will not self test during engine running with a code 67.

Another thing to watch out for when fault finding an XG.

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Had some goodies arrive.....
51d4ee078887f9556c9decdf193e8933.jpg
That's my new Rotor caps and Rotor buttons. Spares now as my problem is solved.

I have fixed my hesitation on acceleration in the XG.
It was the fuel filter, must of been clogged enough just to struggle under load.
When more fuel was demanded the fuel filter was blocking up. Was after market sintered metal type, now banished.
Replaced with new standard Ryco fuel filter.

Another thing to replace.....there is a connector between the fuel pump and hard line in the tank, that with age can fail and leak, replace with a piece of efi fuel line and clamps. Will keep proper pressure in lines after the pump.

Blocked fuel filter also makes for longer/rough crank at starting.

Just goes to show, start with the simple things first. Save yourself time and money.

First check the obvious... Fault codes.
If all clear...11 11 -10- 11 11

THEN
...

Air/Fuel/Spark.

So first check air filter, fuel filter and spark plugs, then work up from there.

Next would be Plug leads/Dizzy cap/Rotor.

That will cost you a max of $250.
You have eliminated the basics.









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Well done Jack, sounds like you've sorted it.. might have to look into those caps and rotors myself, assuming they're the same on xh..
Heya Van,
Yes mate, caps and rotors are same on 6 cylinder XH as XG. Will also fit E series with SOHC motors. :)

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