rough idle 91 lx

[Tannerm]

Friends car. Has a rough intermittent idle. Mods are edelbrock performer heads/cam/intake, 39lb injectors, Exhaust, Powerdyne blower...

Battery is in trunk. He figured it might be a ground issue. He's since fixed this. Then he checked maf. Any clue as to what this could be? Thanks...

[Denny]

Does he have a fuel pressure gauge on it? What's it reading at idle? FMU?

[Tannerm]

He does. In the dash. I'll ask. Fmu?? Pardon my ignorance, it's past my bedtime...

[Z06killinsbf]

Iac

[Denny]

I had idoing issues from the second I had my powerdyne on. Once I took off the FMU and ran an adjustable FPR, it was golden.

What kind of pressure is it reading at idle?

[Tannerm]

Unsure. Haven't got a response from him. This thread might be delayed til this evening. I'm going to bed now... keep the advice coming tho...

[Cobraman]

He does. In the dash. I'll ask. Fmu?? Pardon my ignorance, it's past my bedtime...

Fuel management unit. It is a cheap band aid that allows you to maintain stock fuel pump with a blower. If the car has one, ditch it

[Z06killinsbf]

http://sbftech.com/index.php/topic,1031.0.html

[Denny]

I did that on the Lincoln and it worked great, but I don't think that's his issue.

[Tannerm]

List of crap he did.

1) TPS, replaced and idle voltage reads .96volts, over 4volt at WOT.
2) MAF, unplugged it and fired it back up. No real change, still runs shit.
3) IAC, removed and cleaned, no change. Unplugged and idle suffered more so I ruled that out.
4) Intake, tightened all connections, no found leaks.
5) Cap/Rotor/Plugs/Wires, all new.
6) Injectors, replaced twice.
7) O2 sensors, both new, wiring all intact.
8) Vacuum lines, triple checked and all accounted for.
9) Exhaust, had one loose connection right after O2 sensor, tightened.
10) ECT and IAT sensors, checked with voltmeter, both within range.
11) EGR, I've been told it's turned off in the tune.

[Tannerm]

Fuel psi at the rails is 38-40.

[0393gt]

My car would start to stumble and struggle, at idle, even while driving. Turned out to be the distributor bearings going out and not spinning freely. Replaced all that shit before I figured it out.

[Denny]

Fuel psi at the rails is 38-40.

That seems high for just idling.

[BlueCoupeRedVert]

That seems high for just idling.

Right on target with vacuum discounted.

[Denny]

Right on target with vacuum discounted.

Did I miss that part?