2000RPM "rev limiter" problem + overheat. HELP!

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TurboRex90

Golden EG
Why does my car overheat in about 5 minutes after startup, and hits a "rev limiter" at about 2000 RPM?....Having just rebuilt my engine with all new internals, the Wiring harness is the stock harness for my 1990 CRX Si, but the engine is a D16Z^ out of a 1994 Civic Si. The previous owner had the care running before and i dont see why it shouldnt now. We removed the engine to rebuild it, put it back in and connected 99% of all wires, especially the bare essentials. I have a brand new P28 ECU, an OBD0 to OBD1 harness it in and a brand new Distributor. Now the car starts easy and idles about 1k RPM but it hits a rev limiter at 2k and it overheats in about 5 minutes. Yet brand new Thermostat and everything. THough before we took the engine out, the few times we ran it it overheated also, so i just dont know. Three Honda enthusiats including myself and my father/broother with 10+ yrs of knowledge cant figure this out. please help asap..
 
check for a clogged cat, or clogged muffler. try unbolting the cat and running it like that (just to see if it runs. dont be the jackass running around with an open exhaust through my neighborhood at 1am.)
 
no CEL's at all? like Ef said. it might be an auto ecu. if there is a "Check Engine Light" then you need to find out what code is popping. but being your using a P-28 in a CRX. theres no jumper wire, nor a flashing light on the ecu. so. plug the old ecu back in and check your codes. If you get a "crankshaft position sensor" then you have what i had. and in that case replace your dizzy.

for the overheating. did you bleed the coolant system? you know. that little bleeder valve right there on the water neck at the front of the engine. if theres not on there. then you need to find a water neck that has a bleeder valve on it. and bleed the system.

my CRX did that. overheated quick. and z6's have a tendancy to warm up really quick.
 
no no no the engine is a OBD1 D16Z6, it needs the P28, i got it special ordered for my motor and no its not auto its manual. i also got a conversion harness made. so far the CEL codes im reading are; 9, 14, 21, 41... it did read 5 and 8 but we fixed that. and i know what all 4 codes mean. i dont have my o2 sensor in cuz i have a downpipe. my vtec soleniod is wired correctly and works, we tested with a 12v charge. as far as the CYP sensor and the IAV sensor. no idea what they are actually. and by quick overheating. i mean. within 10-15 minutes it almost hits red. and thats not normal, i have a new thermostat. good waterpump. no leaks in the rad. new coolant. i dont have a clue. and yes we bled the system of all air. and no im not gettin a "crankshaft positioning sensor" its a brand new dizzy for the motor.

*EDIT* and also i cant use the old ECU, cuz the dizzy on it before was bolted on with washers. AKA not right and the ECU doesnt run the new Dizzy. so it has to be this ECU and dizzy. they are new.
 
and by quick overheating. i mean. within 10-15 minutes it almost hits red. and thats not normal, i have a new thermostat. good waterpump. no leaks in the rad. new coolant. i dont have a clue. and yes we bled the system of all air.

i have this problem in my car with my z6 if i sit at a stop light or something for too long.
as long as im moving and air is running through my radiator im fine though ... maybe this is your problem as well?? couldn't know until you get it running right though =/
 
didn't you say you were using the stock harness from the 90 crx?? maybe using the obd0 wiring with the obd1 ecu is causing the problem??
 
Make sure the ground to your tranny is connected properly.
My dad replaced $1000 worth of stuff to fix all his codes that popped up and they still did.
Until he asked me to help and I reconnected his ground and the codes disappeared.
its probably something real simple that u overlooked.
 
A lot of people have that problem becuse the get an auto ECU by mistake.


Its not an Auto ECU, that i'm sure of. and the stock harness was doctored up when the original owner did the swap. i myself changed out some things like for the OBD1 dizzy, and as far as the harness and ECU not working together i have the OBD0-OBD1 conversion harness installed.

as far as the tranny ground problem, ill look into that thanks.
would the valve cover ground affect it? ive yet to ground that too.
 
this blows. its been 2 days and yet no more posts... cant anyone give me ideas that i can try.. besides like the 2 plausible ones.. PLEASE PEOPLE I NEED MY CAR DONE.. and i cant take it to a shop at this point..
 
fuel problem : it s maybe not that but if the fuel pump is dying .... it could do that ?
 
sounds like car maybe running in limp mode... u may have a sensor crossed or somthing? any check engine? Or is the harness hacked so bad something may have crossed when u took it out. Gotta love the ghetto swaps u see all the time.. HACKS
 
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