2.0l fuel injected engine surge starve cycle? Options

[jdlmodelt]

I finally got the ignition and fuel pump hooked up on my 76 2.0 L and the engine cycles between reving and stalling when I hold the pedal down to get a fast idle. What do I need to be checking now?

[tod914]

Pinched line, clogged filter, filter on backwards, lines routed wrong (engine bay feed and return swapped). Have you tried putting a pressure gauge on to see what it is? You can pull the line off the cold start valve and hook it up there. 29-30 pounds. Can also check inside your gas tank for crud and a clogged stainer sock. Valves adjusted properly? Timing and dwell correct? Idle air screw on the throttle body, have you tried turning that up? You also have an adjustment on your ECU. Clockwise enriches, counter clockwise leans. That typically has a melted in hashmark for where the factory setting is.

[jdlmodelt]

Pinched line, clogged filter, filter on backwards, lines routed wrong (engine bay feed and return swapped). Have you tried putting a pressure gauge on to see what it is? You can pull the line off the cold start valve and hook it up there. 29-30 pounds. Can also check inside your gas tank for crud and a clogged stainer sock. Valves adjusted properly? Timing and dwell correct? Idle air screw on the throttle body, have you tried turning that up? You also have an adjustment on your ECU. Clockwise enriches, counter clockwise leans. That typically has a melted in hashmark for where the factory setting is.

where is the adjusting screw on the ECU? There is a trim pot on the wiring harness back near the rear of the passenger side of the engine with a wire disconnected.

I hadn't thought about the timing. Good call on that...I just assumed that the PO hadn't changed anything while the motor was out of the car but he did change all the vacuum hoses. SO, I'll check timing and all hoses while I'm at it.

Thanks for the refresher...I haven't had to tune an engine in years. I used to do it all the time.

[jdlmodelt]

Pinched line, clogged filter, filter on backwards, lines routed wrong (engine bay feed and return swapped). Have you tried putting a pressure gauge on to see what it is? You can pull the line off the cold start valve and hook it up there. 29-30 pounds. Can also check inside your gas tank for crud and a clogged stainer sock. Valves adjusted properly? Timing and dwell correct? Idle air screw on the throttle body, have you tried turning that up? You also have an adjustment on your ECU. Clockwise enriches, counter clockwise leans. That typically has a melted in hashmark for where the factory setting is.

where is the adjusting screw on the ECU? There is a trim pot on the wiring harness back near the rear of the passenger side of the engine with a wire disconnected.

I hadn't thought about the timing. Good call on that...I just assumed that the PO hadn't changed anything while the motor was out of the car but he did change all the vacuum hoses. SO, I'll check timing and all hoses while I'm at it.

Thanks for the refresher...I haven't had to tune an engine in years. I used to do it all the time.

The fuel pressure holds steady around 30psi at the driver's side injector fuel rail.