My1st

I haven’t driven the car much sense I put the HSR on and now realize there’s a problem. If I start out slow and gradually give it gas it runs great. I was on the freeway for the first time the other day and going 65 mph and I put the hammer down and the engine started to cough and gained no rpm’s? Once again if I ease into the gas it runs just fine even at high speeds.
With an HSR do I need a different fuel pump?
Is this a lack of fuel getting too much air?
I think I have another knock sensor code which would make #3 if this one is bad.

AGENT 86

Does sound like a fuel delivery problem. Do you have a fuel pressure gauge ?

C409

......... Sounds like a tune problem ...................... Time to become one with your laptop .........

qws

Start with checking your fuel pressure. You may want to learn how to datalog.

85MikeTPI

^^^

x2

383vett

Here is where a wideband recording would really help. With a wideband, when you punch it, the motor appears to be getting too much or too little gas. One run with a wideband will answer your question.

My1st

Okay time for an education. *****, what is a wideband?

Agent I do have a FPG on the fuel rail. Just went out and fired it up and at idle it’s only running about 33 and goes down to 31 when revved. Looks like I better start with a fuel pump. Is one brand better than another?

383vett

A wideband is an oxygen sensor that can read greater parameters than the stock narrow band which is good only aroung 14.7. A wideband will give you an accurate reading if your air/fuel ratio is at 10 or 16 while a narrow band won't. Couple that with a system that allows recording, it makes tuning or troubleshooting easy.

pkazsr

I use a Racetronics FP, I would replace the regulator while you are there.
(Sorry for butting in)

yedister

Let back up a bit, why is your fuel pressure so low? The standard operating operating pressure your injectors is probably around 43.5 PSI. Set your pressure to around 45 psi because 43.5 is a pain in the *** to set when my gauge reads in 5 psi increments. Do this at idle, slowly open the throttle body and watch the gauge, look for how steady it drops and the response time for the pressure to get back to where you started. Then repeat it faster, go from idle to full throttle. Could be that your pressure was set too low or FPR is in need of servicing. you have to remember that air goes in faster than the fuel, that why you have to account for the lag time for the fuel to play catch up. Every regulator has a dead band / lag time to response to changes, usually most people set the pressure a higher to offset the lag.

My1st

Does anyone make a direct fit replacement FPR for the HSR other than Holley?

rodj

What most use on a HSR as a replacement for the troublesome ( commonly leaks ) Holley AFPR

http://www.kirbanperformance.com/pro...R+%236547.html

qws

I replaced my kirban with a Aeromotive. I do have the kirban if your interested.