I have a 91 crx si with b16a1 and a pr3 ecu. It seems to lack power and fuel cutoff occurs at 7400-7500 rpm instead of 8000 or beyond. Is something wrong with my ecu? Maybe it's from an automatic? I get no check engine lights or anything. I don't know, I'm just looking for an answer. Thanks in advance.

 

If it cuts out at 7500, then you have an auto PR3. You can post up the ECU stamp numbers here and we can tell you if it's auto or 5-spd, but most likely you have an auto PR3. Chipping it will solve your problem, as it'll run like a 5-spd with better fuel & timing maps.

 

Here are the numbers that are on my ecu:
37820-PR3-J50
411-204079AP

What exactly distinguishes the manual from the auto?
Thanks

 

OK, I just popped open the ecu and on one of the circuitboards AT is stamped. So I guess there's my problem.

 

auto to manual conversions on the ecu are easy.

-PHiZ

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PHiZ &raquo;</TD></TR><TR><TD CLASS="quote">auto to manual conversions on the ecu are easy.

-PHiZ</TD></TR></TABLE>

explain please

 

I have automatic ecu also in my hatch I"m about to chip it in like a week. Yeah it sucks, I haven't seen 8000 in two years. Yeah I"m lazy so what. Specially when the chips only cost $50 for two with directions.

 

converting an auto ecu to a manual ecu is very simple, you just adjust a resistor network.

Whups, sorry, I'm thinking OBD1, rumor has it, that if you drop a racing ROM into your ecu, they have disabled checks for ... like auto tranny lockup solenoid, so you may be able to get away with just doing a software conversion.

-PHiZ