Fordmods Logo

Engine idle stumbles exactly 1min 35sec apart????Fixed- 

 

Page 1 of 1 [ 12 posts ] 

 
 Post subject: Engine idle stumbles exactly 1min 35sec apart????Fixed-
Posted: Wed Jul 23, 2008 10:07 am 
Getting Side Ways
Offline
User avatar

Posts: 887

Joined: 8th Aug 2006

Ride: Falcon

Location: Central Highlands
QLD, Australia

Had this problem for a while, basically at operating temp when the car is in drive/neutral/park at idle the engine will stumble at 1min 35sec intervals. The ISC then kicks in and picks up revs. Have used a stop watch and always exactly the same time.

Any idea's, i am thinking MAP sensor or ECU because they use timing circuits?

Cheers.....

 

_________________

97 EL Fairmont 4l OHC .Silver.
Exhaust: Pacemaker's, 2.5" exhaust and Hiflow cat
Intake: FRAM AIRHOG , EL GT snorkel
XR6 300kpa fuel reg Stg 2 Auto Shift Kit.6DJA ECU
PM in Qld looking too buy Toyota 4*4 SR5 Dualcab Hilux 91-97 with 2.8l diesel engine/5spd manual

Last edited by EL__Fairmont on Tue Aug 05, 2008 8:19 pm, edited 1 time in total.

Top
 Profile  
 
 
Posted: Wed Jul 23, 2008 6:24 pm 
Oompa Loompa
Offline

Posts: 38

Joined: 23rd Jan 2008

Location: bris
QLD, Australia

Purge from the fuel charcoal thingy??
Top
 Profile  
 
 
Posted: Wed Jul 23, 2008 6:30 pm 
Getting Side Ways
Offline
User avatar

Posts: 887

Joined: 8th Aug 2006

Ride: Falcon

Location: Central Highlands
QLD, Australia

Masier wrote:
Purge from the fuel charcoal thingy??


So this is normal to happen?

All do i need to replace something. No petrol smells in cabin from a/c etc. So it must be working.

 

_________________

97 EL Fairmont 4l OHC .Silver.
Exhaust: Pacemaker's, 2.5" exhaust and Hiflow cat
Intake: FRAM AIRHOG , EL GT snorkel
XR6 300kpa fuel reg Stg 2 Auto Shift Kit.6DJA ECU
PM in Qld looking too buy Toyota 4*4 SR5 Dualcab Hilux 91-97 with 2.8l diesel engine/5spd manual

Top
 Profile  
 
 
Posted: Wed Jul 23, 2008 6:56 pm 
Getting Side Ways
Offline
User avatar

Age: 34

Posts: 741

Joined: 29th May 2007

Ride: EF XR8 347

Power: 232 rwkw

Location: Perth
WA, Australia

turn off your air conditioner? :P

 

_________________

347 XR8 Build Thread

Top
 Profile  
 
 
Posted: Wed Jul 23, 2008 7:15 pm 
Getting Side Ways
Offline

Posts: 2448

Joined: 5th Nov 2004

Gallery: 7 images

Location: Brisbane
QLD, Australia

I think you'll find that the ECU is moving the engine into rich or lean territory, hence the stumbling. o2 Sensor, or Floating Earth would be normal problems. Also have you modified the engine at all?

Nigel
Top
 Profile  
 
 
Posted: Wed Jul 23, 2008 7:38 pm 
Getting Side Ways
Offline
User avatar

Posts: 887

Joined: 8th Aug 2006

Ride: Falcon

Location: Central Highlands
QLD, Australia

Nigel wrote:
I think you'll find that the ECU is moving the engine into rich or lean territory, hence the stumbling. o2 Sensor, or Floating Earth would be normal problems. Also have you modified the engine at all?

Nigel


Yeah that actually makes sense!

The engine internals are stock. Just got pacemakers, high flow cat, exhaust and intake mods. The 02 sensor was replaced about 40000km ago. It may have failed again? Although last time it failed the idle was really bad when coming too a stop, this is a bit different. Although similar.

The engine at operating temp will idle perfect for about 1min 10secs then progressively get worse then stumble. ISC then picks up revs. And the process starts all over again.

I have checked for vacuum leaks, tightened the bolts on the inlet manifold, checked the MAP sensor hose etc.

What earths should I check- battery to block, engine to floor plan etc..?

Cheers..

 

_________________

97 EL Fairmont 4l OHC .Silver.
Exhaust: Pacemaker's, 2.5" exhaust and Hiflow cat
Intake: FRAM AIRHOG , EL GT snorkel
XR6 300kpa fuel reg Stg 2 Auto Shift Kit.6DJA ECU
PM in Qld looking too buy Toyota 4*4 SR5 Dualcab Hilux 91-97 with 2.8l diesel engine/5spd manual

Top
 Profile  
 
 
Posted: Wed Jul 23, 2008 9:24 pm 
Getting Side Ways
Offline

Posts: 2448

Joined: 5th Nov 2004

Gallery: 7 images

Location: Brisbane
QLD, Australia

Id check all of them - battery to block, block to body, body to Battery.

And possibly also the ground for the ECU wherever it happens to be
Top
 Profile  
 
 
Posted: Thu Jul 24, 2008 7:00 pm 
Getting Side Ways
Offline
User avatar

Posts: 887

Joined: 8th Aug 2006

Ride: Falcon

Location: Central Highlands
QLD, Australia

Checked earths all good >1 ohm difference between block/battery and body/battery.

Ran error ecu code test.

Engine on Test- Code 111 (All good) although the engine was stumbling

Engine Off test- Memory Code 578 (ECU reference voltage low)

What should I check, gregory's manual say it's to do with the auto box.

Oxygen sensor is fine watching go from 0.8V-0.1V in the range. But just as the engine begins to stumble the oxygen sensor drops down to 0.1v and lower for about 10secs then the ISC cuts in, picks the engine revs up and it starts again at 0.85V and cycles through the range again. This repeats itself.

So the ECU is switching from lean to rich mode.

Any idea's

Cheers

 

_________________

97 EL Fairmont 4l OHC .Silver.
Exhaust: Pacemaker's, 2.5" exhaust and Hiflow cat
Intake: FRAM AIRHOG , EL GT snorkel
XR6 300kpa fuel reg Stg 2 Auto Shift Kit.6DJA ECU
PM in Qld looking too buy Toyota 4*4 SR5 Dualcab Hilux 91-97 with 2.8l diesel engine/5spd manual

Top
 Profile  
 
 
Posted: Sat Jul 26, 2008 8:04 am 
Getting Side Ways
Offline
User avatar

Posts: 887

Joined: 8th Aug 2006

Ride: Falcon

Location: Central Highlands
QLD, Australia

I have bumped up the base idle by 100rpm and replaced the fuel filter. It's now running sweet at idle. No more hickups.

New Post::: Bumping up the base idle was a bandaid solution, it's started too do it again a week later!!

Cheers.........

 

_________________

97 EL Fairmont 4l OHC .Silver.
Exhaust: Pacemaker's, 2.5" exhaust and Hiflow cat
Intake: FRAM AIRHOG , EL GT snorkel
XR6 300kpa fuel reg Stg 2 Auto Shift Kit.6DJA ECU
PM in Qld looking too buy Toyota 4*4 SR5 Dualcab Hilux 91-97 with 2.8l diesel engine/5spd manual

Last edited by EL__Fairmont on Sat Aug 02, 2008 9:54 pm, edited 1 time in total.

Top
 Profile  
 
 
Posted: Sat Aug 02, 2008 9:52 pm 
Getting Side Ways
Offline
User avatar

Posts: 887

Joined: 8th Aug 2006

Ride: Falcon

Location: Central Highlands
QLD, Australia

Started playing up again but it's now 2.10mins apart running 95 ron, injection cleaner and new spark plugs. Although the idle got worse at operating temp since fitting the new plugs. Any advise.......

Cheers..........

 

_________________

97 EL Fairmont 4l OHC .Silver.
Exhaust: Pacemaker's, 2.5" exhaust and Hiflow cat
Intake: FRAM AIRHOG , EL GT snorkel
XR6 300kpa fuel reg Stg 2 Auto Shift Kit.6DJA ECU
PM in Qld looking too buy Toyota 4*4 SR5 Dualcab Hilux 91-97 with 2.8l diesel engine/5spd manual

Top
 Profile  
 
 
Posted: Sat Aug 02, 2008 10:15 pm 
Smokin em up
Offline
User avatar

Age: 49

Posts: 298

Joined: 23rd Nov 2007

Gallery: 5 images

Ride: 03 BA

Location: st marys
NSW, Australia

injection cleaner is crap, take it to a machanic an get injectors cleaned proper, a mate of mine had done same an it purrs now. cost abt $200 but worth it on many ways. response, fuel eco, quicker, an so on
Top
 Profile  
 
 
Posted: Tue Aug 05, 2008 8:24 pm 
Getting Side Ways
Offline
User avatar

Posts: 887

Joined: 8th Aug 2006

Ride: Falcon

Location: Central Highlands
QLD, Australia

Problem is fixed. Found 3 loose bottom bolts on the pacemaker extractors. Tightened them up and the idle is good again and no more stumble.

Put a multimeter back on the oxygen sensor and it is switching between 0.1v-0.8v as per normal.

Basically what happened is that unmetered air upstream of the oxygen sensor was making it show a lean reading and thus ecu was making adjustments to try to compensate.

 

_________________

97 EL Fairmont 4l OHC .Silver.
Exhaust: Pacemaker's, 2.5" exhaust and Hiflow cat
Intake: FRAM AIRHOG , EL GT snorkel
XR6 300kpa fuel reg Stg 2 Auto Shift Kit.6DJA ECU
PM in Qld looking too buy Toyota 4*4 SR5 Dualcab Hilux 91-97 with 2.8l diesel engine/5spd manual

Top
 Profile  
 
Display posts from previous:
Sort by  
 Page 1 of 1  [ 12 posts ] 

Who is online

Users browsing this forum: No registered users and 17 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

 

 

It is currently Sat Dec 16, 2017 12:51 pm All times are UTC + 11 hours

 

 

(c)2014 Total Web Solutions Australia - Australian Web Hosting and Domain Names