H/I install troubleshooting.. fuel delivery issue?

[jb89coupe]

Just finished installing my heads, intake, injectors, and afpr. The car is sluggish and jerky until about 2800rpm, then it kicks in suddenly and throws you back in the seat, pulls like crazy way up past 6k. I think I'm leaning out at the bottom of the rpm range. I tried bumping the fp up to 50psi.. it got better for a while and then went back to doing it after a few minutes.

See my sig for details (more in my garage), the injectors are bosch 4-way 19#'s. Just out of curiosity I hooked up my old pro-m 75mm bullet and mac cai - it doesn't do it as badly with that setup, but it still hesitates at the bottom of the gears.

Anyone have any suggestions? Am I looking in the wrong place with the fuel pressure, could it be something else? I have 2 new bosch o2 sensors, tps is set properly, new iac and ect sensors.. can't think of anything else. Could a vacuum leak be causing this?

 

[jerry beach]

Sounds like TPS, did you check it for smooth movement throughout its entire range with an analog voltmeter? The auto parts store should test it for you if you ask them.

 

[jb89coupe]

Sounds like TPS, did you check it for smooth movement throughout its entire range with an analog voltmeter? The auto parts store should test it for you if you ask them.

The tps works fine, I had it on the car before the H/I install, and I tested it afterwards. I do have another laying around I could (and will) try, but it seems that the problem wouldn't be specific to a certain rpm range if it was the tps. The car is mushy, unresponsive, and sort of stutters up until about 2800rpm, under both full and partial throttle (you can even feel it under deceleration). At 2800 or so it litterally kicks in suddenly and throws you back. I'm a little stumped, seems like if I wasn't getting enough fuel I would be lean at higher rpms instead of lower..

 

[jerry beach]

Have you tried backing off the timing?

 

[jb89coupe]

The lower we go on the timing the worse the bottom end gets. Is it possible the dist is off a tooth or something?

 

[jb89coupe]

Bump, the car is not shooting any error codes.. anyone?

 

[mackey]

If the distributor is off a tooth, it would run horribly, and I doubt you could get it started and running right. It is worth a try though.

 

[jerry beach]

Does it idle fine, or is there a miss present? Try pulling the plugs and see what they tell you.

 

[DMAN302]

Get a fuel gauge on it to see if FP is cresting properly with RPM. Check for vac leaks, check your hego (02 sensor ground orange on back by firewall, and other grounds back there for good connection. Next you may need to check firing order..it will run OK if you use non HO order. Then you may want to swap out the TFI or get it checked out. You can not be a "tooth" out on the EFI engine..either 180 out or is correct..juding by the fact the car runs..you're not 180 out.

 

[jb89coupe]

Bump..
Grounds are good, firing order is correct, don't have a vacuum gauge but I've done the carb spray test in a bunch of places and haven't found a leak. It idles fine but seems like it might be missing under load until around 2800-3000rpm and takes off like a bat out of hell after that. Plugs and wires are new.. same dist/tfi/coil from before the swap, worked fine.. I know the heads and intake may have killed a bit of my low end but the car is definately choking up, not just lacking power.

 

[jb89coupe]

bump.. no one on here has had a similar problem?