Please help I'm at witts end. I just got 3/98 24valve and I'm trying to find out why it starts it right up, idles great and when you give it throttle in park for drive don't matter Motor doesn't go above 1500rpms . Got a code reader and it came up with what seems to be Dreaded P1689 code

Which far as.I can find is something NO ONE agrees on of the cause!!

I found this site from another diesel guy and I link I was given was here for 24valve 50\51 engine/obdii-error-codes94/P1689no-communication-between-ecm-and-vp44-r35/

 I went through link and was able to get all way to #5 test which is checking ohms between #2terminal on FORM which is Supposed to be a "White Wire" and #13 on the ECM harness connector. 

Well I don't have a White Wire anywhere in the rpms harnes. So I can't go beyond this test

At my shirts end and really don't want to have to pay mechanic $200 just to tell me what's wrong then whatever it will be on top of that. 

Really need help

 Also in reading and watching, remember something about it after fuel filter change that whatever is wrong will make it super hard to start. Getting fuel bled and fired up again. Now after changing fuel filter now seems that I'm having that issues also.( Battery started to run down so couldn't crank a lot to get fuel back up. After full day doors.open key switch on off alot .

Had to stop and charge up battery. I might get it started but still don't know why it not acting like the Raped Ape a 2nd Gem is Supposed to Be!!

Help please

Only has 113845 miles on it . Transfer pump relocated to in fuel tank. 

Not sure what other help I can give at.moment. I need help though

Like most of us I ain't got a lot in life  good wife great.daughter, he'll of a dog and not much $ especially just to have someone say it's this part that be $200 oh and if you want me to fix it, it will be X amount times 3 more plus cost of part

Y'all know the deal?

Thanks in advance for Any help

2 hours ago, dripley said:

Correct me if I am wrong, you only have the 1698 code right? 

 

Yes @dripley iHave 3 codes I  total P1689 P1698 P1693.

That's why I'm asking about.the mods.also on order of which to start tackling these.codes. I think the 1689 is main culprit and I think that's preventing most of my issues. And then other.are.side.effects

 But not sure,  that's why I asked @Mopar1973Man in last.post. But still not sure about anything when it comes to diesel so far lol

 

The 1693 you can forget about. Fixing the others will make that one go away. You will have to go thru the diagnostics for the other 2. This is what you would pay a shop to do if you dont. The electrical system on these  old trucks get a bit quircky with age. Connections can get dirty or loose thru out the system. Take the 1689 and work thru it. Dont get hung up on wire color, test between the pins called out. 

Me I hate electrical problems. Dealing with some of mine have made get into it more and clean things up a good bit. Did that and  the WT ground mod to help prevent future problems. 

 

There is no mahic bullet here and the parts that might be bad are expensive. 

eviltwisted1

 

My apologies, I had typed a reply that seemingly didn’t post. I did send a message to your Facebook account too. Nice work by the way, I used to help a friend of mine do that here where I am. Ultimate Concrete, it was called. Gratifying work. 

 

I would do the W-T ground mod for sure, it doesn’t take a lot of time and it’s worth the effort, If not for anything but to forces you to know the electrical side of these things, which you’re going to want to know anyway if you plan on keeping it. 
Also take the ground underneath your drivers battery tray apart. Mine looked good at first glimpse. So much so I put it all back together. Couldn’t sleep and woke up the next morning to take the battery tray back out again and look at the wires. There is 11 grounds on one stud. 
I had to cut back about 6-8” on most to find good copper to solder to. I’ll include a picture. 
Neither of those helped fix my P1689....but no doubt it will save me a lot of headaches down the road....and definitely should have been done.
 

What did fix my code for now and at least a few starts (no driving yet) giving me the first glimpse of hope in the last couple of weeks was something in the 11 pin connector on the middle of the firewall (the one with the lock on it). I took this connector apart, probed for ground and 12v etc. 
Put it back together cleared my code and voila. Code was gone, check engine light too. It would start but still not rev over 2000rpm. In Park. However...
Pulled it into neutral and no problems. Full throttle and rpms. 
Speaking with mopar1973man there could be something still going on with the neutral safety switch and the torque management system, not quite sure yet as I’m still celebrating my small victory in this fiasco and having full throttle and no p1689

 

I still have a 1693 companion code because one of our local transmission companies at one point cut one of the wires going to the transmission...it’s been that way since, I’m in the process of trying to decipher which one because it didn’t need to be done.
The transmission wouldn’t upshift. Only had first and reverse. Their fix was to cut a wire, charge $700 and then blame it on the “truck side of things”. This was under warranty at the time btw. 
I left pissed, bought another rebuilt transmission from a different company and put it in myself. That was two years ago and it’s never missed a beat. Figure I may as well fix the wire they cut if I can find it as it definitely wasn’t the problem and perhaps be code free  

For now I’m happy that the p1693 doesn’t set off the CEL. I hate a dash that looks like a Christmas ?. 

 

Edited April 23, 20205 yr by Brooks

@Brooks man that's awesome new. I checked all the pin on firewall but I disnt see anything wrong there by eye.sight. I didn't try probing anything( as I had and have No clue on what to even peobe or what I would be looking for there!! Thank God! I got another job started today so I'm on that for next few days, but I hope by monday I'll be able.to work on truck again.  1st thing is I'll do test moparman advised then I'll so the Mods. I'm curious to see.what I find when I dig.in a little farther into this thing. 

Ya know what alao. I have Not tried.it in neutral or drive since I have tested and rest apps and all that . So maybe just maybe that might be a hope.for me!

 I'll make sure.i do test.1st and check it and mods and if not better I'll try neutral ( maybe it's the neutral safety switch or something. 

Is there way to clear.ths codes without a code reader?? I took my cheap $60.00 1 back after I got mad it didnt do live data or better than what it was.

Or am I better just to bite bullet and buy decent reader that will do live data?? Is this worth.while investment? 

Thanks again 

Ps what name do I need.to look for on fb I didnt see fei2nd request or anything I'll look and see.of its somewhere hiding.

 

Sounds exactly like what my truck did when the Edge boost fooler wasn’t working

Edited May 6, 20204 yr by ColoradoColt