GreenF350
Member
I had another thread going about the problems I'm having with my truck, but wanted to take it in a bit different direction and get more specific so I'm starting another one.
The quick background is I just did new injectors, UVCH's, studs, springs, etc. Since that work I have developed a random and intermittent check engine light that comes on everytime I drive it. It will come on for 3-5 seconds and go back out....usually does that 2 or 3 times in a row and then stays out for the rest of my drive (40 miles one way). It seems to run fine, starts up very quick. Does haze a little when first started, but clears up when warm and there is a bit of a debate as to whether it's normal or not, but I think it idles rough and cylinder rotational velocity change indicates that I may be right. That being said, I want to concentrate on the check engine light and try and eliminate any electrical gremlins for now and make sure that isn't causing my problems since the check engine light is a new development since I did the injectors and other stuff.
I've pulled codes numerous times and always get a P1316, that is the only code in the PCM. I know that means there are IDM codes and from what I have found searching the proper way to get those is run a buzz test. The only code I get from a buzz test is a P1668 and that code has shown up after buzz tests since I bought my Scangauge years ago. What I don't understand is why is that code setting my check engine light now? I've found this in regards to the P1668 and figured I might as well chase it down and eliminate the possibility that is causing the check engine light.
FJ1 DIAGNOSTIC TROUBLE CODE (DTC) P1670 and P1668
DTC P1668 and P1670 indicates that a communication error has occurred between the PCM and the IDM.
Possible causes:
Open fuse
IDM relay
Open or shorted IDM enable circuit
Open/short in EF circuit
Open/short in FDCS circuit
IDM powering circuits
PCM
Check for other codes.
Key on, engine off.
Perform KOEO On-Demand Self Test and retrieve Continuous DTCs.
Can anyone help my identify which wires I need to be checking continuity on for the IDM enable circuit, EF circuit, FDCS circuit or IDM powering circuits? I probably won't dig into it until this weekend, but gathering info right now. Is it possible that something else it setting the check engine light but not showing up when pulling codes? Other than checking wires, I'm not sure where to go from here. Since it runs I would assume that the fuse and IDM relay are probably good, but I will look at them too just to be sure.
-Aaron
The quick background is I just did new injectors, UVCH's, studs, springs, etc. Since that work I have developed a random and intermittent check engine light that comes on everytime I drive it. It will come on for 3-5 seconds and go back out....usually does that 2 or 3 times in a row and then stays out for the rest of my drive (40 miles one way). It seems to run fine, starts up very quick. Does haze a little when first started, but clears up when warm and there is a bit of a debate as to whether it's normal or not, but I think it idles rough and cylinder rotational velocity change indicates that I may be right. That being said, I want to concentrate on the check engine light and try and eliminate any electrical gremlins for now and make sure that isn't causing my problems since the check engine light is a new development since I did the injectors and other stuff.
I've pulled codes numerous times and always get a P1316, that is the only code in the PCM. I know that means there are IDM codes and from what I have found searching the proper way to get those is run a buzz test. The only code I get from a buzz test is a P1668 and that code has shown up after buzz tests since I bought my Scangauge years ago. What I don't understand is why is that code setting my check engine light now? I've found this in regards to the P1668 and figured I might as well chase it down and eliminate the possibility that is causing the check engine light.
FJ1 DIAGNOSTIC TROUBLE CODE (DTC) P1670 and P1668
DTC P1668 and P1670 indicates that a communication error has occurred between the PCM and the IDM.
Possible causes:
Open fuse
IDM relay
Open or shorted IDM enable circuit
Open/short in EF circuit
Open/short in FDCS circuit
IDM powering circuits
PCM
Check for other codes.
Key on, engine off.
Perform KOEO On-Demand Self Test and retrieve Continuous DTCs.
Can anyone help my identify which wires I need to be checking continuity on for the IDM enable circuit, EF circuit, FDCS circuit or IDM powering circuits? I probably won't dig into it until this weekend, but gathering info right now. Is it possible that something else it setting the check engine light but not showing up when pulling codes? Other than checking wires, I'm not sure where to go from here. Since it runs I would assume that the fuse and IDM relay are probably good, but I will look at them too just to be sure.
-Aaron
