HELP:Wont rev past 3K????????

k, here goes. i’ll give everyone the vitals. just completed ls/vtec into 91 ls. running 95 gsr head & dist. on a 91 ls block. PR3 ecu reprog’d for ls/vtec. same gsr injectors, msd cap & coil.

starts up fine now, but when you peg the throttle quickly, she sputters to catch up. revved up slowly, wont go past 3K. sort of hits like a rev limiter???any ideas?

ECU: getting code four.(four fast blinks) means crank angle sensor i believe. checked all the sensors inside the dist with ohm meter, all reading between 350-700 ohms. also getting good fuel pressure 48-49 psi. and good spark at the plug.
i have no idea what is wrong with her now. supposed to have an acura mechanic come over monday to look at her. one thing i could think of is the gas has been sitting in the tank for a good 5 months, but wouldnt it run $hitty all the time, not just at 3K?

thanks guys!!

hey glad to hear u got her started
i would find another pr3 or any compatible ecu and plug it in just to see what happens

i agree, with that try another computer

I experienced a similar problem. I dropped a 1.6 multi port engine in a dx civic. we were forced to use the dx distributer until we found a 1.6 one. The dx distrbuter has no #1cylinder positioning sensor and it only revved to about 3K.

If your getting a code 4, look deeper into the problem. The wiring between the sensor and the ecu.

Good luck

My guess would be the distributer or the ecu. You said you were running a 95 GSR head and dist. Well the dist is OBD1 while the PR3 is non OBD…(My friend’s teg wouldn’t go pass 3k when he was using a 92 dist in a 90 teg). Also the GSR head has secondary buterflies so I think you would need the P72 ecu that regonizes that, unless you had them removed.


yeah, i’m running a skunk2 IM, with no butterflys. PR3 was supposed to be prog’d for ls/vtec. i will try my PR4 original ecu tommorow. thanks guys, i’ll keep you updated.


Yes, the ecu should run with no problem. Its the distributor, if u used one from anything other than a non obd car it not goin to run correct. obd1 needs obd1 distributor…non obd needs non obd dist. etc


i thot not revving past 3k was a definite sign of ecu problem. wrong program, bad solder joints, etc. sorry i dont know jack about swaps but i read that hint while reading about ecu upgrades.

k, acura mechanic came over to my house today, looked at everything, we tried both ecu’s, with the same problem. we have narrowed down the problem to: #4 code is the crank angle sensor, so, the ecu sees the wrong sensor from the ditributor. the ecu then thinks this baby is at 8000 rpm, and , in turn, the rev limiter kicks in at 3250 rpm. BAM! so , i guess i gots to re-do my wiring from the distributor to the ecu. i’m getting an inline code checker from there tommorow. now, i’m pretty sure that is the problem.
the problem lies in the fact that a gsr distributor will not plug into the harness of my 91 ls. so i was forced to cut and splice one of the plugs. that is where i messed up. oh well, i’ve learned alot of stuff during this damn swap. but i know it will be sweet in the end.