Codes

[steven89]

I have codes 12, and 51. The car idles at 500rpms.. and it seems like it has no power.. just finished doing a HG change.. Maybe a boost leak? but not sure about the codes and idle..

Thanks in advance!

 

[jetjock]

Likely a problem with the CPS or it's wiring there Sparky. Get rid of the 12 first and the 14 might follow. If not come back.
Clear them first and each time you try something.

 

[steven89]

Likely a problem with the CPS or it's wiring there Sparky. Get rid of the 12 first and the 14 might follow. If not come back.
Clear them first and each time you try something.

sorry, it doesnt have 14.. it was 12 and 51.. used to have 14 but i manage to clear that one by fixing the timing..

 

[jetjock]

Hmmm, timing won't fix a code 14 but if it's gone it's moot. Hey, at least you got it to start. That's more than I can say for many people here who do head gaskets.

The code 12 is CPS related. The 14 is usually igniter related but it can also be CPS related because of how the ECU processes faults. A "real" 14 will shut the engine down. Btw, always repair the lowest code first.

Clear the code and try again while messing with the CPS wiring. If the CEL comes on and the code comes back (or the engine stops) you've found it. Next try measuring the pickup coil resistance. Did you have the CPS open when you had the motor apart? They can get pretty gunked up inside if the seal fails.

After you get that taken care of fix the 51 by adjusting the TPS. Be sure the AC is off if you have it. Then check and set timing because if you set timing with a 51 it'll be wrong. Only after all this should you tackle the idle problem but that'll probably go away with the 51. See, a 51 with a closed throttle means your idle speed control system isn't working, among other things.

 

[steven89]

Thanks man,
I wiggled this old splice in the CPS wiring and now 12 is gone. 51 still there.
I'm gonna solder this wiring splice instead of the twisted together it is now.
CPS cover was off when I set the timing the first two times - it was actually pretty clean inside.
Should I still measure the pickup coil resistance? If so how? What should it be?
Then I guess it is the TPS - I got no idea how to do that one. Any tips?

 

[steven89]

I wiggled this old splice in the CPS wiring and now 12 is gone. 51 still there.
I'm gonna solder this wiring splice instead of the twisted together it is now.
CPS cover was off when I set the timing the first two times - it was actually pretty clean inside.
Should I still measure the pickup coil resistance? If so how? What should it be?
Then I guess it is the TPS - I got no idea how to do that one. Any tips?

anyone?

 

[jetjock]

Here's a tip: Get out of the car repair biz

Since the code 12 is gone forget about the CPS pickup coils. If you need to measure them in the future it's all spelled out in the service manual.

TPS adjustment is also shown in the book. First a little about code 51 and what causes it. 51 is usually caused by the idle switch in the TPS not being on when the throttle is closed. This idle switch is used for several things. The two you're concerned with are idle speed control and ignition timing. When the switch is open the idle speed system is disabled. After all we don't want the ECU trying to control engine rpm when we're out driving around. The second problem is when the switch is open the ECU won't freeze ignition timing when you jumper the diagnostic block. That's why if you set timing with a 51 it'll end up wrong when you're done.

First make sure the throttle isn't sticking. When you're sure it's closed loosen the two screws holding the TPS and adjust it slightly by twisting. Follow the procedure in the book or tweak the TPS until the Check Engine Light stops showing 51 and starts a fast blink. What you want is a fast blink with the throttle closed and 51 when it's just cracked. You can get away with this because 51 is the only code that never gets stored in ECU memory. It's "real time" for lack of a better word ie; it'll automatically clear when the problem causing it goes away. Just be sure the air conditioner is off because it'll also cause a 51 if it's on. After you get the TPS set try it and you'll see. Finally, the engine doesn't have to be running to do any of this stuff.

Check your timing after all this is done. If you can't get rid of the 51 post up and I'll tell you what to do next. I'm cutting you some slack here. Next time either try a search or reading the manual. This has all be covered a bazillion times. And fix the CPS wiring right. Twisted wires. To the EFI system that's like putting duct tape over a hole in a person's heart. Someone needs to be slapped.

 

[steven89]

Thanks a bunch. Sorry im so bad at this. I'm only 17 and im trying my best. I did look through TSRM (guess i just suck at searching through em) but i just couldn't find TPS or TPS adjustment..

I also did not do the CPS wiring, if you look in my sig i haven't had the car for long.. But i know for sure now that this car has a JDM 7m in it and whoever did the swap must have just twisted together the wiring. Ima try what you said and then get back to ya.

Thanks a bunch again!!

 

[jetjock]

Don't be sorry. I have a gruff exterior but inside I'm all marshmallow. There's more than one owner here who could confirm it if I let them. I know you're only 17 and doing your best, it's why the Old Coot (tm) is willing to help. Do what I said and report back or PM me if you need more info.

 

[steven89]

Ok, got the TPS code to go away i now have fast blinking (or i guess.. no codes). It does throw 51 if i hit the gas, so i guess thats the way it is supposed to be... It still idles real low, like 500-450 would the timing sort that out?

Update - Fixed timing, idles a lil above 500 (according to tach). Now it revs freely, when i looked at the timing after taking out the diagnostic jumper it seemed like it liked to be at 12* I had it set at 10* with the diag. jumper in.

Now im going to change oil, solder the CPS wires, and put the timing cover back on and see what she does on the road.

Thanks again Jetjock!!

 

[jetjock]

10 is fine. It's normal for timing to move around when the jumper is out so don't worry about it. A little above 500 isn't too far off. You really need an external tach to be sure. Be patient. The ECU will need a little time to collect the learned idle values it lost during the time it was without power.

A few things you can do: Turn on the AC or headlights and see if the idle increases. With the headlights it'll dip then come up, with the AC it should jump right up as soon as you push the button. Also listen for the idle speed motor to click a few times just after you shut the engine off. The idle should be high when the engine is started cold and gradually come down as it warms up. If all that checks out the idle speed system is working.

Be sure all the vacuum lines are connected properly and all the clamps on the induction system are tight. Leaks are unlikely to be related to low idle but checking for them will prevent grief later on.