Misfire and hesitant power - Intermitent
Misfire and hesitant power - Intermitent
Author
Discussion

JAMESCMR2

Original Poster:

713 posts

208 months

Wednesday 1st July 2009
quotequote all
Hi all,


This will cover topics previously discussed but some more specific questions was the reason for this post.

Thanks in advance for any help, this forum seems to me to be the most helpful one i've ever been on, so much knowledge out there.

Ok, to the point.



My symptoms appear to be the classic ones for replacement fuel filter, spark plug gaps, collapsing LP fuel hose (between filter and pump) or electrical breakdown somewhere!

The problem only seems to be there when the heat soak has set in.

I checked the spark plug gap, 35thou so looks ok.

just now removed the fuel filter and, classic, suspect hose. fuel filter looks ok but will post pics to get opinions asap, as i have no previous experience of a good condition one. The fuel pipe had me confused... i read this post

www.pistonheads.com/gassing/topic.asp?h=0&f=26&t=604792&mid=95549&nmt=misfire%20-%20fuel%20starvation?

and looked at the pics of this persons fuel system behind the wheel arch liner. mine appears to be different.
The fuel pump was mounted to the floor pan (not vertical) and the end fitting for the suspect fuel pipe was a straight not a 90 banjo (i guess because of the different mounting position)! this meant the fuel hose had a better routing to the pump and i imagine would not collapse in the way others have.

Is this a standard fit or has this been done in the cars previous life?

the fuel pipe looks to be the standard stuff, my next plan was to replace the pipe with upgraded parts. Cheap and can't hurt i guess.

I also think the fuel pump might be an upgrade or different part but what is the best way to tell?

Where specifically should i be looking next if a new pipe and filter yield no better performance?



Thanks to all

JAMESCMR2

Original Poster:

713 posts

208 months

Friday 3rd July 2009
quotequote all

Come on guys, where's the responses...

changed the filter but can't get hold of any pipe, anyone point me in the direction of a supplier please?


How do you put pictures on this forum??

Gadgeroonie

5,362 posts

265 months

Friday 3rd July 2009
quotequote all
reduce the gap to about 25/28 thou and see if problem goes away

where are you based ?

daddysumo

2,545 posts

242 months

Friday 3rd July 2009
quotequote all
JAMESCMR2 said:
Hi all,


This will cover topics previously discussed but some more specific questions was the reason for this post.

Thanks in advance for any help, this forum seems to me to be the most helpful one i've ever been on, so much knowledge out there.

Ok, to the point.



My symptoms appear to be the classic ones for replacement fuel filter, spark plug gaps, collapsing LP fuel hose (between filter and pump) or electrical breakdown somewhere!

The problem only seems to be there when the heat soak has set in.

I checked the spark plug gap, 35thou so looks ok.

just now removed the fuel filter and, classic, suspect hose. fuel filter looks ok but will post pics to get opinions asap, as i have no previous experience of a good condition one. The fuel pipe had me confused... i read this post

www.pistonheads.com/gassing/topic.asp?h=0&f=26&t=604792&mid=95549&nmt=misfire%20-%20fuel%20starvation?

and looked at the pics of this persons fuel system behind the wheel arch liner. mine appears to be different.
The fuel pump was mounted to the floor pan (not vertical) and the end fitting for the suspect fuel pipe was a straight not a 90 banjo (i guess because of the different mounting position)! this meant the fuel hose had a better routing to the pump and i imagine would not collapse in the way others have.

Is this a standard fit or has this been done in the cars previous life?

the fuel pipe looks to be the standard stuff, my next plan was to replace the pipe with upgraded parts. Cheap and can't hurt i guess.

I also think the fuel pump might be an upgrade or different part but what is the best way to tell?

Where specifically should i be looking next if a new pipe and filter yield no better performance?



Thanks to all



Your setup sounds standard. I would look at the pipework exiting the filter to the pump carefully and if still on standard pump and wiring this might also be an issue on full chat.

Steve

JAMESCMR2

Original Poster:

713 posts

208 months

Friday 3rd July 2009
quotequote all
thanks for responses. will give the gap a try.

So is it worth replacing the wiring to the fuel pump? where do the two wires originate?


i'm based in Newcastle upon Tyne, bit out the way


James

NobleGuy

7,133 posts

244 months

Friday 3rd July 2009
quotequote all
How long does the hesitation last?
The fuel system in general seem to be cropping up as a topic a lot recently, but my blip in power a couple of years ago turned out to be a corroded coil.

And where have all the old posts gone? confused
There have been loads of threads on topics like these over the years that have just gone by the looks of things...

ThatPhilBrettGuy

11,810 posts

269 months

Friday 3rd July 2009
quotequote all
NobleGuy said:
And where have all the old posts gone? confused
There have been loads of threads on topics like these over the years that have just gone by the looks of things...
Really confused Nothing has been deleted.

leemullan16

53 posts

209 months

Friday 3rd July 2009
quotequote all
is it the 2.5 gto?? mine was and in the end i cut vents into the bodywork and the problem has been solved. i put a temp sensor into the fuel tank and the fuel was getting up to 50 degrees in the tank!! by the time it got to the fuel rail in must of been vaporising! i fitted to vents on the engine bay and the problem has never come back. before i done this i replaced my plugs and put a new coil pack on it.
Hope this helps

NobleGuy

7,133 posts

244 months

Friday 3rd July 2009
quotequote all
ThatPhilBrettGuy said:
NobleGuy said:
And where have all the old posts gone? confused
There have been loads of threads on topics like these over the years that have just gone by the looks of things...
Really confused Nothing has been deleted.
That's weird. After the maintenance done about a year ago a load of the old posts were unavailable in the search. For example, I posted a topic about hesitations about 18 months to 2 years ago but it doesn't come up. In fact, only topics from around the end of 2008 come up despite me selecting the "8 years" option on the dropdown (is that new - I thought it only went up to 2 or 3 years?).

Air Support

511 posts

238 months

Friday 3rd July 2009
quotequote all
Got to agree with NobleGuy

I've been looking for info on the Oil cooler and Intercooler mods.

Just tried a search and even with the new 8 year option I can find nothing before December 08

S26VE P

2,174 posts

271 months

Friday 3rd July 2009
quotequote all
NobleGuy said:
ThatPhilBrettGuy said:
NobleGuy said:
And where have all the old posts gone? confused
There have been loads of threads on topics like these over the years that have just gone by the looks of things...
Really confused Nothing has been deleted.
That's weird. After the maintenance done about a year ago a load of the old posts were unavailable in the search. For example, I posted a topic about hesitations about 18 months to 2 years ago but it doesn't come up. In fact, only topics from around the end of 2008 come up despite me selecting the "8 years" option on the dropdown (is that new - I thought it only went up to 2 or 3 years?).
This one?

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

JAMESCMR2

Original Poster:

713 posts

208 months

Friday 3rd July 2009
quotequote all
its a GTO3


Got some new fuel pipe from one of the suppliers to the firm i work for. As a free sample. gonna fit that this weekend and see how i get on. (its very high pressure PTFE braided hose. very flexible and incredibly high heat resistance). if it works on the short hose section i may try and replace the whole lot at some point.

still haven't had the opportunity to try the car, after heating up and on full tilt, since replacing the fuel filter yet though.

if this doesn't work i guess i'll have to look electrics.

hoping to get it on the rolling road if i can sort this stuff out!


NobleGuy

7,133 posts

244 months

Monday 6th July 2009
quotequote all
S26VE P said:
NobleGuy said:
ThatPhilBrettGuy said:
NobleGuy said:
And where have all the old posts gone? confused
There have been loads of threads on topics like these over the years that have just gone by the looks of things...
Really confused Nothing has been deleted.
That's weird. After the maintenance done about a year ago a load of the old posts were unavailable in the search. For example, I posted a topic about hesitations about 18 months to 2 years ago but it doesn't come up. In fact, only topics from around the end of 2008 come up despite me selecting the "8 years" option on the dropdown (is that new - I thought it only went up to 2 or 3 years?).
This one?

http://www.pistonheads.com/gassing/topic.asp?h=0&a...
How the flying f*** did you get that? smile
What did you put in as the search?

Seriously, I can't find it... paperbag

I used "hesitation" in the top box of the advanced search, selected the Noble forum in the list and chose '5 years' on the dropdown.

leeshell

278 posts

229 months

Monday 6th July 2009
quotequote all
I had backfires when starting and had "hesitant power" when accelerating. After I had the air intake replaced after exploding from a backfire I was left with hesitation.

For me, this was resolved by cleaning the corroded ECU connector and I had to reset the adaptive map.

HTH Lee