Sometimes struggles when WOT.

[listy]

To start, its an NA-TT JSpec 1993.

 

If I put my foot to the floor from low revs (circa 1200-1500) sometimes the engine struggles to pick up, and kind of jolts and kangaroo hops. Doesnt do it all the time, but only every so often.

 

Now, I'm no expert, but my mate said he was having fuel map problems in his Skyline, and it got me thinking.

 

Could this be caused by the fuel pump being on its way out? Or the fuel filter getting a bit clogged up? Or even the fuel map itself (I dont think its this, as its stock ECU).

 

Now, I know people are going to say "change the pump and filter, at least then they are ruled out", which is my plan anyway.

 

Just wondering really if the knowledge I have gained from this forum has led me to a good chance of being right

[pedrosixfour]

Pump is a good bet, the originals are getting on a bit now. I noticed the same behaviour when I put my old pump back into the track car just to move it around until my new 340lph Aeromotive unit arrived.

[James]

To start, its an NA-TT JSpec 1993.

 

If I put my foot to the floor from low revs (circa 1200-1500) sometimes the engine struggles to pick up, and kind of jolts and kangaroo hops. Doesnt do it all the time, but only every so often.

 

Now, I'm no expert, but my mate said he was having fuel map problems in his Skyline, and it got me thinking.

 

Could this be caused by the fuel pump being on its way out? Or the fuel filter getting a bit clogged up? Or even the fuel map itself (I dont think its this, as its stock ECU).

 

Now, I know people are going to say "change the pump and filter, at least then they are ruled out", which is my plan anyway.

 

Just wondering really if the knowledge I have gained from this forum has led me to a good chance of being right

 

I'm NA-TT as well and sometimes have the same problem. Only when not fully up to temperature though.

 

How often does the fuel pump need changing? I have a Walbro 255 which was fitted about 4 years ago.

[Alex]

From your garage I suspect you're on the stock ecu with a stock fuel system?

 

If so yes I would suspect a fault more than a bad map. I don't think you've done enough to upset the stock map.

 

If you're about the change the pump then there's not much point speculating beyond that. Once the pump is in (and I would change the filter too if it's more than 4 years old) then you can got at it. Air and Ignition systems can cause similar issues...