Car Bogging between 2k - 3.5k rpm

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Fastlane
0.1 Bar Boost
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Joined: Tue Mar 04, 2008 1:11 pm
Car: S13
Location: Durban

Car Bogging between 2k - 3.5k rpm

Post by Fastlane »

Hi guys,

Any helpful feedback will be appreciated.

My SX (CA18det) bogs between about 2000 to 3500 rpm when I try to floor it, then moves when it boosts.

It also feels sluggish when driving out of boost - no power.

I have fitted a ''300lph 6 bar'' no name brand fuel pump in December but the problem persists.
FP Guage is at 2.8 bar at idle and drops to 2.5 bar under load. Is this normal?

I disconnected the FPR and it makes no difference?!? Still behaves the same.

Moved CAS a bit (advanced) and it seems to be a bit better (only just).

Motor was completely rebuilt about 950km ago. Mechanic omitted Knock Sensor. Is this okay???

Help Please!!!
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Charlvdw
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Engine: SR
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Post by Charlvdw »

Fuel related. You should have 3,6 bar on idle and it should go up when you rev the car, not down.
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Daniel
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Real Name: Daniël
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Re: Car Bogging between 2k - 3.5k rpm

Post by Daniel »

Fastlane wrote:Hi guys,

Any helpful feedback will be appreciated.

My SX (CA18det) bogs between about 2000 to 3500 rpm when I try to floor it, then moves when it boosts.

It also feels sluggish when driving out of boost - no power.

I have fitted a ''300lph 6 bar'' no name brand fuel pump in December but the problem persists.
FP Guage is at 2.8 bar at idle and drops to 2.5 bar under load. Is this normal?

I disconnected the FPR and it makes no difference?!? Still behaves the same.

Moved CAS a bit (advanced) and it seems to be a bit better (only just).

Motor was completely rebuilt about 950km ago. Mechanic omitted Knock Sensor. Is this okay???

Help Please!!!
What do you mean by this?
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Charlvdw
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Joined: Wed Jan 09, 2008 10:08 am
Car: S13
Engine: SR
Location: Pretoria

Post by Charlvdw »

Sorry 2,6bar on idle and the go up.
Fastlane
0.1 Bar Boost
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Joined: Tue Mar 04, 2008 1:11 pm
Car: S13
Location: Durban

CA Bogging

Post by Fastlane »

Thanks for the replies guys.

@ Daniel : The Mechie said that he did not fit the Knock sensor because it did not do any good when the motor blew the first time around. I don't know if I agree with his reasoning. I do have the knock sensor. Should I fit it?

@Charlvdw : What should the Fuel pressure go up to at W.O.T.?
I have just ordered a Walbro Fuel Pump from Duane (Team Obsession).

Any theories on the FPR???
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Grobblere
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Post by Grobblere »

Personally i think its your knock sensor. Without it the ecu goes into limp mode to protect against detonation, your mechanic's theory really sucks. :D
These cars might be old but the ecu's are not 2 far behind...its not a golf esse :-)

If your pressure drops then your fuel pump cannot supply as it should. Your Fpr shouldn't give problems easily and also your description does not really fit a faulty fpr.

Im going to remove my knock sensor tomorrow and check if i can find an alternative.....
:D
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300sx
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Post by 300sx »

@ Daniel : The Mechie said that he did not fit the Knock sensor because it did not do any good when the motor blew the first time around. I don't know if I agree with his reasoning. I do have the knock sensor. Should I fit it?
lol, i cant believe some people.. how about we remove your afm too, i mean its only a restriction...
300zx fairlady 1991
200sx s13 with vg30det @ 1bar
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Grobblere
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Post by Grobblere »

remove your car wheels, they just create rolling resistance :twisted: :roll: :wink: haha
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Daniel
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Post by Daniel »

Yeah if there's no knock sensor it will run pretty crap.

You can also bypass the sensor using a 470k resistor to ground :wink:
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Fastlane
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Car: S13
Location: Durban

Bogging

Post by Fastlane »

Sheesh :roll: Thanks guys, that really helps. Ha Ha Ha, let's just remove the engine etc. as it just adds weight to the car, ha ha ha.
It is already obvious that I don't agree with the Mechie's decision about omitting the knock sensor, but will the lack of the knock sensor cause the symptoms I've previously described.

Thanks for your positive contributions Daniel. Much appreciated.

Anything further with regard to the behaviour of the car when I removed the vacuum pipe from the FPR. (I'm also not sure, but it seems that the said vacuum pipe connects at the other end to a source that's located just below/on the ignition module.)
Lindt
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Post by Lindt »

the fpr on the s13 is connected to a hot start solenoid, make sure that thing is working as it's cuts the vacuum line to the fpr
Fastlane
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Joined: Tue Mar 04, 2008 1:11 pm
Car: S13
Location: Durban

Bogging

Post by Fastlane »

''Hot start solenoid''???, sorry I'm not familiar with this. where or how can I check this? Is it located near or on the ignition module?
Fastlane
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Joined: Tue Mar 04, 2008 1:11 pm
Car: S13
Location: Durban

Sorted!!!

Post by Fastlane »

Okay, installed a Walbro 255lph Fuel Pump on Friday evening, and the car feels so much better. Just need to check and adjust timing and base idle, maybe set CO's.
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