Hi! Thanks for helping me out in advance.
I have a 1991 Civic Si with a DOHC ZC and a PM7 ecu to go with it. Now, I have 4 codes that are being thrown, and I'm a little confused about them. Can some one give me some insight as to why I am getting the following?

- code 5: MAP sensor
- code 7: TPS sensor
- code 19: Lock-up Control Solenoid
- code 20: Electronic Load Detector (ELD)

Now the problem I am having is this; I just bought a new TPS, so im assuming there is a fault in my wiring (I can track that down.), but 19 and 20 are completely new to me. I dont understand why I am getting code 19, I thought that was only for Auto transmission cars? And code 20 I have no idea where to start.

Any help would be GREATLY appreciated! Thanks for your time guys!

 

try this for code 20
https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/91-civic-eld-code-20-burnt-up-my-alternator-2941237/

it can be as simple as replacing your underhood fusebox entirely

 

You have an auto ECU whether you like it or not.
ELD code is usually because you missed a ground.
Check your thermostat grounds and the transmission to chassis ground.

TPS and MAP may be miswired, but it may clear if you missed the sensor ground.

 

Hey guys, thanks a million for the speedy response.
So I have a auto ECU eh? damn. I was really excited when I got this thing, pm7's are hard to find. the side of it reads, PM7-905; doesnt the 0 mean its a Manual transmission ecu? I guess not if its giving me the lock-up code. Can anyone confirm this is the case; that code 19 is a result of an auto ecu in a manual car??

As for the ELD, thanks for the reference 91efbluehatch. Ill give that a go. It only started happening when I swapped my chipped pm6 for the pm7.
as for the map and tps sensors, I guess ill trace them back to the ecu and check the wiring for faults or problems.

Again, thanks a million gents.

 

code 19 ONLY appears when the ecu cannot find up the lock up control solenoid on an auto transmission. A 5 spd ecu will not look for that solenoid...sounds like you need to get the ecu converted to 5 spd.

 

Hey sorry for bringing this back up, but I have a quick question. Im buying what I have been told is a manual PM7 ecu and I want to clarify something before I purchase it.
Is this the best ECU for my DOHC ZC? Not entirely sure what gen it is, but here's a pic to identify...



The Manifold is stamped PM7, along with other components so I assume a PM7 ecu will be best.
My main concern is the efficiency of the engine; with a PM6 I failed my emissions test 10-fold! I assume the appropriate ecu will correct that??

Anyways, thanks in advance for the input!

 

PM7 is the correct ECU for that engine

 

Perfect. thanks for the speedy response. I currently have a pm6 in, but I think its causing me to fail the emissions test hideously. Will a PM7 ecu correct the emissions by much??
Thanks again!

 

My car actually PASSES on a PM6 ECU (Cali smog too). Maybe there's something else wrong?

 

damn it. No mines failing by like 30times the allowed levels even with a brand new cat on it. What could possibly be going that??! I thought the PM6 would be causing irregular fuel timing and consumption and that the PM7 would fit it.

 

Just having my distributor clocked a few degrees off made my zc blow dirty . A good indicator is idle speed . It should be very low . If that fails . Buy methyl Hydrate . Run the tank dry and put a gallon in . works for me everytime.\

Ps : right after fill the tank up with reg gas that stuff eats up rubber seals.

 

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