got a code 18 and 33, need some help curing them

[blue83ranger]

I'm getting my '86 ranger ready to go back on the road after a year of being "parked" (moded) and i checked it for codes and got 2 and i can't seem to figure out how to fix them. I got a code 18 which i found to have more than one meaning. Like invalid service code, no tach signal, spout circuit grounded, etc. and a code 33 EGR opening not detected. I'm kinda thinking the code 18 caused the code 33 because i took the egr off, put a vac. pump on it and could see it open and stay open with vac. on it. and it opened smoothly. I put vac on the green egr line and the red line and they both hold a vac. as does the vac. canister. I also checked the wiring to the sensor that gives the EGR vac. and it has power. The only thing i don't know how to do is check the exhaust back pressure sensor, assuming that has something to do with it as there is no other electrical sensor around the egr. so that brings me to code 18. I have no idea what to do to fix it. Back in 2002 we replaced everything electrical in the dist. and I just unhooked the TFI and the plug and wires look great. and the spout plug is installed and is making contact and is good. anyone know how to fix a code 18? thanks for any help even any complete guesses are welcome.

 

[HndMeDnBroncoII]

I'm getting my '86 ranger ready to go back on the road after a year of being "parked" (moded) and i checked it for codes and got 2 and i can't seem to figure out how to fix them. I got a code 18 which i found to have more than one meaning. Like invalid service code, no tach signal, spout circuit grounded, etc. and a code 33 EGR opening not detected. I'm kinda thinking the code 18 caused the code 33 because i took the egr off, put a vac. pump on it and could see it open and stay open with vac. on it. and it opened smoothly. I put vac on the green egr line and the red line and they both hold a vac. as does the vac. canister. I also checked the wiring to the sensor that gives the EGR vac. and it has power. The only thing i don't know how to do is check the exhaust back pressure sensor, assuming that has something to do with it as there is no other electrical sensor around the egr. so that brings me to code 18. I have no idea what to do to fix it. Back in 2002 we replaced everything electrical in the dist. and I just unhooked the TFI and the plug and wires look great. and the spout plug is installed and is making contact and is good. anyone know how to fix a code 18? thanks for any help even any complete guesses are welcome.

how does the truck drive even just unplugging a sensor can trip the codes
i would clear the codes (remove bettery ground for five minutes)
and then drive it see if the check engine light comes on after that and go from there

 

[blue83ranger]

If i remember right i think ever since I've had the truck (2000) it always had those codes i just never could get them to go away. and i read the symptoms of the code 18 and it has them all. (dies, hesitates, sometimes idles rough) and i've had the battery out many times, sometimes for days at a time.

 

[HndMeDnBroncoII]

If i remember right i think ever since I've had the truck (2000) it always had those codes i just never could get them to go away. and i read the symptoms of the code 18 and it has them all. (dies, hesitates, sometimes idles rough) and i've had the battery out many times, sometimes for days at a time.

That sucks the egr should have a vaccuum control solenoid of some sort that operates it so follow the vaccuum lines from the egr. alot of times the egr is always good but the solenoid fails.and all your symptoms do sound
like the egr it might be getting power but it could still be faulty
grab one from the wreckers and try it
other than that i would double check your timing
actually set #1piston to tdc check the cam and crankshaft gears
and dist position maybe something is quite lined up perfectly
or the timing chain needs to be replaced i have seen motors that sometimes are really just bloody finicky

good luck though
roger

 

[holyford86]

the meaning of the code 18 depends on what test it came from, KOEO,KOER or CM. without knowing where it came from I would test the IDM resistor and see if it is anywhere close to 22k ohms, if it isn't go to radioshack and get a 22k resistor in the highest wattage rating you can and solder that in there in place of the old one, the IDM resistor likes to hide in the wire harness right behind the power steering pump. I wouldn't count on the timing chain being bad. close to 279k on my motor and it still runs pretty good, the motor has never been apart either.

 

[blue83ranger]

The timing chain should be good to go. Right before i got the truck the previous owner had the engine rebuilt but then his daughter rolled it. So i got the truck and put a good 2wd body on it. I'll check that resisor, i remember seeing it many times. thanks

 

[Kyle M.]

If you have an EFI computer controlled engine, a code 33 is what you want if you delete the EGR. If you dont' get that code, and have deleted you EGR, you will have other issues. Code 18, I'm not sure, but I check and make sure you spout connector is in place.

 

[blue83ranger]

i tested the resistor and i didn't have a needle close by so i just tested it from the TFI plug to the coil and another plug that goes in the cab, all the wires were green with a white wire and there was no resistance at all.

 

[blue83ranger]

do you know what watts i should be looking for? I didn't get a chance to go by a radioshack but my dad went and said the biggest one he could find was something like 1/2 of a watt. He figured that was to small so he didn't buy it.

 

[blue83ranger]

i finally got the resistor and it didn't help the way it runs. When i first start it and put in gear it'll die. and even when it's warmed up if i either put it in gear and let it idle it'll start stumbing and most of the time it dies. Or if i put a small load on it (tow something) with low throttle it'll act the same way. In the upper rpms it's fine. When it gets warmer out i'll test for codes again. and see if the computer knows something i don't.

 

[blue83ranger]

i just tested for codes and the resistor cured the code 18 but i still have a code 33. I did some searching and found a guy with a similar problem to mine and another guy suggested the knock sensor might have problems. has anyone heard of that before?
Just to review a code 33 is EGR opening not detected. And i used a vac. pump and all of the lines to/from the egr are good, to/from the EGR actuator are good, all lines to/from the engine are good. Using the pump on the EGR itself makes it move and hold a vac. endlessly. port from the EGR through the intake are clear, and the tube from the manifold to the EGR is clear and exhaust does move through the tube. any suggestions at all are welcome, because i'm out of ideas.

 

[Kyle M.]

code 33 wont hurt anything. It will just shut the EGR valve funtion off in the computer. You can drive it and have no issues. If you have a CEL on, you can get that to shut off by using a simulator. I made one using this picture

All that will cure is the CEL but not the code, but it is OK to have that code 33. My guess would be the EGR sensor is bad if you really want to fix it.

 

[blue83ranger]

i don't have an EGR position sensor. The only thing i have with wires on it touching any part of the EGR is a black box with a hose coming off it going to the exhaust side of the EGR, I guess sensing the exhaust pressure from that small tube coming from the manifold. and the solenoid that gives the EGR vacuum. I don't see any wires not hooked up and nothing obviously missing. I have a few 2.8's and it's obvious that they have an EGR position sensor but the EGR on them is pretty different.

 

[Kyle M.]

I guess you are right, sorry about that.