Hessitation past 4K RPM.. Help..

[E30_fiend]

After reading the thread I was going to ask which plugs you used but then you answered the question.

Those two, three and four prong plugs are a joke. No good for any car. Just a marketing scam. People automatically think,"more prongs equals more spark which equals MOAR POWA!" But in reality, electricity finds the closest route to ground. It will choose its path down one prong and keep using it. Rendering the other prongs useless.

Glad you figured it out though.


Taylor

[BMWLOCO]

Thanks to all..

So far, after the new single stem plugs, the car is running better. I ordered a new FPR and put that in this AM and went for a long drive. A few WOT pulls, and etc..

The car is running good. No hesitation, and no sputtering. I think I'm good..

More updates as needed.. Thanks again!

[jlevie]

What you need to do is to see what the rail pressure is when the engine is misbehaving. Tee a pressure gauge into the rail feed line and zip tie the gauge to the driver's windshield wiper.

[IRON-E]

Maybe I'm just reaching but how about the AFM? It could be clogged too. Check for busted fuel lines, and vacuum leaks.

[jlevie]

Sputtering at high rpm and it dies? A possibility would be a clogged exhaust. Remove the o2 sensor and take it for a spin. Let me know...

A better test is to temporarily replace the O2 sensor with a pressure gauge. Anything over 1.5-2psi back pressure is bad.

[maximapitko]

Sputtering at high rpm and it dies? A possibility would be a clogged exhaust. Remove the o2 sensor and take it for a spin. Let me know...

[BMWLOCO]

did you try changing the main relay? just a thought, but i had one go bad intermitantly and it had the same effects your describing.

I replaced the main relay with another one laying around that I pulled form a junkyard a month ago. It ran good for a few days, and went out again. I'll swap the old one back in to check.

Thx..

[BMWLOCO]

Pull the plugs when your car dies...I bet they are completely wet because of the 19# injectors.

This started BEFORE I put in the Mustang Injectors. I'll pull them to see if that's an issue regardless.

Thx..

[I got it, yes!!]

did you try changing the main relay? just a thought, but i had one go bad intermitantly and it had the same effects your describing.

[dnguyen1963]

Pull the plugs when your car dies...I bet they are completely wet because of the 19# injectors.

[BMWLOCO]

UPDATE:

FFWD a month and the car sat for a while because of a few days off and driving the MCoupe.

A few weeks ago, I bought a new IGNITION COIL, and put it in. Drove it for a few days and all went smooth, maybe a fluke. The day before I went on leave, (14 May), I was driving back from work and it died. No more WOT sputtering, but a huge fuel smell.

I parked the car for about 10 days and yesterday I bought a Mustang O2 Sensor and retrofitted it a few hours ago. Car idles well, take it out for a drive, and a few WOT runs, pull the corner around the house and the car dies again. No sputtering, just dash lights on, and it doesn't want to start again.. Cranking, etc... but no ignition.

Fuel on the reserve, but I pull the back seat and check for fuel-pump operation and it's turning on, but no start. Let it cool off, and still no start. WHAT GIVES?

The only thing that I haven't replaced in the engine is the plug wires, and the fuel pressure regulator.

Thoughts!

Thanks in advance..

[BMWLOCO]

No, but will do ASAP. Thanks..

Still, I'm thinking fuel, but will give it a try...

[dnguyen1963]

Have you checked your ignition coil?

[BMWLOCO]

YESTERDAY:

Swapped the FPR from a friends E30 and all sounded good. After I replaced the Throttle Position Sensor with a new one, we dialed it in and voltage is good to go now. Idling is spectacular.

TODAY: Drove it to work. On my way back home, while cruising at 3-4K rpm in 4th,
IT JUST DIES!, I pull over to the side of the road, wait a few seconds and it starts right up. WHAT GIVES!

I was in Air Force Blues and didn't want to get dirty while pulling the lines on the bridge to see if there was fuel pressure from the pump...

Started right up and drove home..

I'm suspecting:
- FUEL PUMP / RELAY ? (Has a new 255LPH pump) ???

So far, New TPS, CPS, newer injectors, and swapped FPR.

I'm stumped!

Thanks in advance!

[BMWLOCO]

I'm swapping the FPR with a friends this AM and will report the findings. Thanks again to all!