Hessitation past 4K RPM.. Help..

[E30-325iS]

I don't think you can just put in Mustang injectors, it'll run too rich unless the ebay chip is programmed for 19# injectors. Make sure that when you are measuring the output of various sensors, e.g cts, tps, etc you also measure at the ecu in case the harness is bad. The connector under the intake manifold is notorious for becoming corroded and causing all sorts of problems.
Before replacing anything else go back to stock and measure every thing again, the DME is probably the last thing to suspect.

[BMWLOCO]

UPDATE:

- Got a new OEM TPS installed. Checked resistance per the Bentley.
- Put in some Mustang Injectors.

Still some hesitation after 4K RPM in 1st, 2nd, etc.. at WOT and sputtering unless I release the accelerator.

On the way home after the repair, It died again. I tried to restart again and it took 3 tries and about 2 minutes of cool-down to start back up.

I'm suspecting the Fuel Pressure Regulator.

When it stalls again, I'll pull the hose that sends fuel to the rail and see if there is pressure. If none, fuel pump/filter clogged. If good pressure to that area, I'll pull the return line to see pressure..

Is the DME a possibility?

Thanks in advance!

[paperplane94]

Check out the bentley manual, might be online somewhere.

[BMWLOCO]

- New 255LPH High flow Fuel Pump
- New Cap and Rotor a few months ago.

I'll check the TPS..

How do I test it with the multimeter? What am I looking at for "Normal" voltage?

Thanks again..

[nomansland92]

Most likely tps but give your cap and rotor a check, Also you could check fuel pressure or your fuel flow rate on your return line.

[paperplane94]

Fellow Enthusiasts:

Stock M20 that when I go WOT in 2nd gear, I get major hesitation past 4K RPM and engine bogs down until I let go of the pedal.

Here's what I've replaced so far:
- Cleaned ICV
- Replaced the Crank Position Sensor (yesterday)
- Spark Plugs less than 1K new
- Wires new
- Replacement Fuel Pressure Regulator (maybe a new one needed)

I'm thinking Injectors.. (They are at least 200K old)
If so, which ones should I buy?

I put in the ebay chip and the problem was still happening BEFORE the chip.

Thoughts..

Thanks in advance..

That screams bad TPS. Test it with a multimeter.

^YOU BEAT ME BY SECONDS :)

[jlevie]

Check the TPS. The WOT switch may be bad. Then check rail fuel pressure while driving the car when the problem occurs.

[BMWLOCO]

Fellow Enthusiasts:

Stock M20 that when I go WOT in 2nd gear, I get major hesitation past 4K RPM and engine bogs down until I let go of the pedal.

Here's what I've replaced so far:
- Cleaned ICV
- Replaced the Crank Position Sensor (yesterday)
- Spark Plugs less than 1K new
- Wires new
- Replacement Fuel Pressure Regulator (maybe a new one needed)

I'm thinking Injectors.. (They are at least 200K old)
If so, which ones should I buy?

I put in the ebay chip and the problem was still happening BEFORE the chip.

Thoughts..

Thanks in advance..