Raising the compression?

gtirx2

Active Member
Out of adjustment throttle body?I am not sure if it would cause your problem but if all else fails it maybe worth a look.
 

antgtir

New Member
gtirx2 said:
Out of adjustment throttle body?I am not sure if it would cause your problem but if all else fails it maybe worth a look.
Would this not effect the full range of throttle position and cause hesitation or a miss fire throughout acceleration?

Ant.
 

gtirx2

Active Member
Tbh i would not really know,i would not think it would afect wot to much but i would of thought it may afect your idle?I am just saying if all else fails it maybe worth a look as i know how annoying misses like this can be;-)
 
A

another sunny

Guest
My R has been suffering with the same fault, i am down slightly on boost as well. The only thing i have noticed is...if i hold the throttle with the revs hovering just above 4k i get a miss and pop , if i put on more throttle it goes away, alsowhen hovering the 4k+ as it misses the vac/boost shoots down , instantly back up as the engine fires again(this all happens within a second or 2, more of a blip than a real drop and up again). I did have a problem before that turned out to be a loos intercooler pipe, i have checked fully this time and no loose pipe. I am hoping to find the fault when i replace the gearbox within the next month or so.
 

zenwahwong56

New Member
Hi

I had a similar situation on my pulsar, and in the end "Maf Sensor" Clean it with carb cleaner, gave my response back up.
Let us know how you get on
 
S

Sam P

Guest
Hi sorry to hi jack the thread but had any1 got any pics of where the MAF and DET/Knock Sensor are???
 

youngsyp

Active Member
Ant,

I had a very imilar problem with mine but, that turned out to be the fuel filter. I'd get a fuel pressure gauge and see what yours stands at, as a start.

Paul
 

antgtir

New Member
youngsyp said:
Ant,

I had a very imilar problem with mine but, that turned out to be the fuel filter. I'd get a fuel pressure gauge and see what yours stands at, as a start.

Paul
How did you test the pressure with the gauge? Was it: -

1. pressure gauge installed before fuel filter
2. pressure gauge installed after fuel filter
3. pressure gauge installed after FPR

Is it an inline installation so you can run the car and read the pressure simultaneoulsy?

Just for information ive checked the resistence across the MAF and its within acceptable limits:roll: :lol:

The saga goes on:lol:

Ant.
 

youngsyp

Active Member
antgtir said:
How did you test the pressure with the gauge? Was it: -

1. pressure gauge installed before fuel filter
2. pressure gauge installed after fuel filter
3. pressure gauge installed after FPR

Is it an inline installation so you can run the car and read the pressure simultaneoulsy?

Just for information ive checked the resistence across the MAF and its within acceptable limits:roll: :lol:

The saga goes on:lol:

Ant.
The pressure gauge will be installed between the fuel filter and the fuel rail.
It will be in line. I.e. pressure gauge attached to an inline adaptor. If you get long enough pipes, you could feed it out of the bonnet and watch it whilst test driving the car.

I bought this kit: http://cgi.ebay.co.uk/FUEL-PRESSURE...ryZ30921QQssPageNameZWDVWQQrdZ1QQcmdZViewItem (with the 100 psi gauge) but, I'm not convinced of it's accuracy as, it read 3.2 bar at idle, with vacuum disconnected on 2 different, stock FPR's !
 

antgtir

New Member
youngsyp said:
The pressure gauge will be installed between the fuel filter and the fuel rail.
It will be in line. I.e. pressure gauge attached to an inline adaptor. If you get long enough pipes, you could feed it out of the bonnet and watch it whilst test driving the car.

I bought this kit: http://cgi.ebay.co.uk/FUEL-PRESSURE...ryZ30921QQssPageNameZWDVWQQrdZ1QQcmdZViewItem (with the 100 psi gauge) but, I'm not convinced of it's accuracy as, it read 3.2 bar at idle, with vacuum disconnected on 2 different, stock FPR's !
I presume the high idle pressure is related to the fact you are testing an injection system and not a carb system? What results did you get and conclusions did you come to?

Cheers for the link.

Ant.
 

youngsyp

Active Member
antgtir said:
I presume the high idle pressure is related to the fact you are testing an injection system and not a carb system? What results did you get and conclusions did you come to?

Cheers for the link.

Ant.
Yep, that's correct. As the fuel system is of the injected variety, pressures will be a lot higher than carb fuel systems.

From memory, the two FPR's both returned 3.2 bar at idle, with the vacuum pipe removed and around 2.8 bar at idle, with the vacuum pipe attached. The pressure also responded as expected, with blips of the throttle.

This led me to believe that the FPR(s) weren't tired and were functioning as they should be. But, the gauge I was using wasn't terribly accurate.

I did this testing to investigate my presumed low fuel pressure issue, that was discovered when the car was on a dyno.
Since taking these measurements, and knowing how well the car runs, the colour of the spark plugs etc... and watching the dyno operator fiddle with the probe, I'm convinced the lambda probe in the exhaust wasn't reading properly and thus, gave erronious results.
They always have issues at MOT time getting a decent reading too so, that further reinforces my suspicions !
 

Dooie Pop Pop

New Member
have you thought about rewiring your fuel pump? it may feel fine above a certain point but tbh its all to easy to get used to the way a car pulls and assume its normal.....

lambda probe is another option;)

are you sure its not Aimee' s moaning everytime you try and boot it which causes your right foot to flutter somewhat:lol:
 

Aimee

Moderators
Staff member
Dooie Pop Pop said:
are you sure its not Aimee' s moaning everytime you try and boot it which causes your right foot to flutter somewhat:lol:

Ha ha ha :lol:

Ant....dont say a word ;-)
 

antgtir

New Member
youngsyp said:
Yep, that's correct. As the fuel system is of the injected variety, pressures will be a lot higher than carb fuel systems.

From memory, the two FPR's both returned 3.2 bar at idle, with the vacuum pipe removed and around 2.8 bar at idle, with the vacuum pipe attached. The pressure also responded as expected, with blips of the throttle.

This led me to believe that the FPR(s) weren't tired and were functioning as they should be. But, the gauge I was using wasn't terribly accurate.

I did this testing to investigate my presumed low fuel pressure issue, that was discovered when the car was on a dyno.
Since taking these measurements, and knowing how well the car runs, the colour of the spark plugs etc... and watching the dyno operator fiddle with the probe, I'm convinced the lambda probe in the exhaust wasn't reading properly and thus, gave erronious results.
They always have issues at MOT time getting a decent reading too so, that further reinforces my suspicions !
Funny you should comment on the Lambda sensor being duff as this year i had to place the CAT on the car for the first time of owning it in order to pass it through the MOT. I thought this was very odd as all other years its flown through with no prob's emission wise.

I wonder actually, i have a small pin prick of a hole at the side of the weld around the nut that sits on the exhaust for the seconf lambda sensor to sit in, i wonder if due to the pressure difference this hole is under pressure and drawing air in which is being registered by the sensor and therefore adjusting the fuelling to suit the air fuel ratio it thinks it is producing? Saying that though the plugs show no signs of over fuelling which in this case i would expect to see?:doh:

I may look into it anyway as it must be large enough as you hear the whistle on full throttle:roll:

Stu: I haven't yet re wired the pump, just installed the Walbro with the OE wiring. Are there any inline fuses or other little gizmos that i need to install in order to protect the pump as with the OE design?

Thanks for the comments chaps.

Ant.
 

youngsyp

Active Member
antgtir said:
Are there any inline fuses or other little gizmos that i need to install in order to protect the pump as with the OE design?


Ant.
You need to stick a fuse no more than 12" from the battery, in the new fuel pump feed. This is to protect the car (fire risks etc...), more than it is to protect the fuel pump.

As for your exhaust leak, the second 'lambda sensor' isn't actually a lambda sensor. It's just a temperature sensor for the cat so, it won't effect fuelling. The hole might effect any emissions readings at the tail pipe though !
 

antgtir

New Member
youngsyp said:
You need to stick a fuse no more than 12" from the battery, in the new fuel pump feed. This is to protect the car (fire risks etc...), more than it is to protect the fuel pump.

As for your exhaust leak, the second 'lambda sensor' isn't actually a lambda sensor. It's just a temperature sensor for the cat so, it won't effect fuelling. The hole might effect any emissions readings at the tail pipe though !
Bollocks, i already knew this but had a blonde moment:doh: :doh: and another for good luck :doh: :lol:

Does the pump not go through a relay of some kind that aids the pump to prime and stop, then feed when required as normal? god i hate electrics lol:roll:

The slight leak cant help things im sure.

Has anyone got a spare Lambda sensor that they know is working that i can borrow to test?

Cheers,

Ant.
 

youngsyp

Active Member
antgtir said:
Does the pump not go through a relay of some kind that aids the pump to prime and stop, then feed when required as normal? god i hate electrics lol:roll:

Cheers,

Ant.
Yep, it will use the stock relay to send the switching supply to a new relay. This will have the full voltage feed from the battery.
Whe you have it all fitted, it will behave as the stock system, with priming when the ignition is switched on, and normal running when the engine is running etc...

Have a hunt around bud, there are a couple of 'how to's' floating around, with a parts list too.

Paul
 
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