86 300z stalls at 2150 rpm

[1mcwrench50]

I'm working on an 86 300z non turbo with a manual trans. It stalls at 2150 rpm, no spark/ injector pulse. It picks right back up as soon as it decreases rpm's (roughly 1600-1800 rpm's). I've replaced the MAF, cleaned the connectors, checked signal to ecm (2.4-3.2 volts dcv @ ecm), replaced coil, power transistor, ecm, fuel pump was below specs/ replaced, new f. filter, ecm, crank angle sensor, pickup, F. pressure regulator, practically everything that could be related, including dropping the exhaust thinking a clogged cat could be creating enough back pressure to activate the rev limiter(?)....no change.
Speaking of the rev limiter, is anybody familiar with this circuit? What wires does it use (part of the Maf circuit?), and how does it work?
Any suggestions, advice, knowledge would be very much appreciated. Yes, we have considered C4 as an option.....

[AZ-ZBum]

It still sounds like a MAF/AFM issue. The rev limiter is not supposed to be activated until you reach 6500 rpms. It's internal to the ECU.

Is the MAF you bought a brand new one? Have you tested your MAFs in known running cars?

[1mcwrench50]

I've tried two remanufactured by NAPA/Echlin....same results. Checked the connections, ohmed it out with dvom from ecm to maf/good, and checked voltage/signal at ecm w/ car running. Signal ranges from 2.4-3.6 dcv.

[stprasinz]

Ive had that same problem at one time I could switch anything to the car nothing helped... then I tried the ecu from my other 300 and it was the ecu.. But I was also told by several mechanics its the only ecu the heard of being bad, and doubted discredited it to something else... One who I saw about once a week or every other week asked me how'd that competer turn out, or did the real problem come back... well I drove the car for? 30,000 without a similar hickup

also had the dizzy go once that acted similar, but it shut off and wouldn't start after about 3 times of turnign it off and back on, which luckily I was home....

but My ecu did the same, acted as the maf even after testing the the maf out and it was good.... just a thought and good luck

[1mcwrench50]

Thanks for your reply. I actually found the problem, but didn't get the chance to post it here. Seems that the previous owner lived in a high crime area.....so he installed his own "Qwik fix" alarm. He ran a set of wires from the tps signal, and signal return about 4" up from the ecm, and installed a switch in line with these wires. That kept the signal from the tps from getting back to the ecm. The switch he installed shorted out, which kept it at 0 ohms (closed circuit). The previous owner did a fine job of hiding his handiwork too. Anyway, as soon as I found that, clipped the wires for the "alarm", zoom zoom....all fixed. What a Royal PIA!!!!