I was playing around with my TPS on the weekend trying to build an adjustable one and I think I may have toasted my engine computer.

My intake heaters don't always come on (its about 0C in Calgary lately), and even when they do its still hard to start so I don't think that the cold start mechanism is kicking in either. Also when I engage cruise control it doesn't hold its speed it accelerates.

From looking in the service manual it looks like all those things are controlled by the ECM.

But all my guages work including speedo and tach.

Anyone blown one before? I currently have my TPS completly disconncected and have a swt on the orange line to the tranny for OD upshift so I don't know if its sending a OD signal.

I'm afraid to ask how much this will cost!

 

Sometimes I wonder if posting mods on a website is the right thing to do. I've seen it a few times on here where someone has tried to modify something like somebody else has done and created potential hazardous situations.
I'm not trying to critisize someones ability or directions, but I see some of us doing things we shouldn't be doing because someone said they've done it.
IMHO I really think sometimes we should wait for someone's specific help to modify our trucks if we don't know EXACTLY what we're doing.
An experiment may cost us all in legislation if we don't be careful what we do.
eg* If we modify a pcm or throttle and the vehicle slams into someone or something, WE ALL know when the cops, lawyers and government find out that this is an everyday event and we're creating a dangerous situation, some political goon or legislator is gonna pass a restrictive law to prevent us from working on our vehicles unless we're licenced and certified.

 

Interesting point from Rob. I don't like what he's saying, but he has a point. Personally, I believe if you are dumb enough to do it, you should be responsible for it -- but it doesn't always work that way, especially these days.

As for the ECM, I wouldn't think it is fried yet. There are a lot of other sensors and wires that affect cold start and the cruise. If I remember correctly, cruise will NOT work without a TPS. If the cold start check light comes on when you first turn on the key, then I would bet it is a problem outside of the ecm too.

Good luck with it.

 

The cruise problem is due to the disconnected TPS. I don't think your PCM is damaged. I think the WTS issues are unrelated to your TPS problems. The most obvious thing to check on the WTS situation is the temp sensor wiring. If the wiring is good check resistance. At room temp it should be around 800 ohms, in ice water it should be around 2k ohms. WTS sensor is the sensor closest to the intake elbow.

 

I know what I said is very controversial, but what would the implications be for the people posting the mods, the people doing the mods or for the website for allowing the mods being performed to be posted?.
In this world today with all the lawsuits happening, who would or could be held responsible?

Posting pics or stock repairs and tips are one thing. I don't think that would be a problem.When we start posting modifications to injection pumps and such.... we may be creating some friction on us.

I just don't want to see a good thing get destroyed.

Just some food for thought. Like I said "DON'T FLAME ME!"

 

If nobody posted anything about modifying these trucks, Jack could run this site off a PC in his basement.

 

I'm not argueing with ya there Dave. I just hope that when we do some of the things we do (re: re-engineering factory products)
that we spend a little extra time and be careful and CERTAIN that what we do is right. If we're not sure, we have to STOP and ask for help and get the right answers.
We take alot of responsibility on ourselves and jeopardize others if we're not careful.

I don't think a little disclaimer at the bottom of the page about the posted repairs/mods/changes will ever make us exempt from legal persecution in the event something goes wrong.

 

Rob,

Valid points, even though I don't totally agree. Humans have been modifying vehicles since they were invented. Its sort of human nature to try to have a hand in improving something. Could be as little as filling up with premium fuels or putting on those expensive wiper blades.

The jeopardizing of the "public" can't be controlled, just ask Audi owners, Ford Exlporers, the infamous Gremlin etc that are/were leathal from the factory.

If you are worried about legal persecution, then you better not drive at all. Heck, stay locked up in your basement....... Break out the foil caps...

 

cLAYH. I did modify....... removed my TPS from the truck and replaced it with a device that works. I used a device that costs about 12.50 USD. There are is one draw back but it does not affect the shift in to OD.

I have run this system for 4 - 5 months now and will never again buy a TPS. The shifts are fast with no hesitation at all.

I used the wiring diagram in the manual and adapted the device to it.

Rammer64.

I have taken the time to research this change over but will not post on the exact steps I took to hook up. Even though this device isn't rocket science it's statements like yours that has made me come to the decision of not posting anymore at all.

Best of luck

Jim

 

I'm not trying to be a fear monger or grim reaper.
My point is this and nothing else.
We had better be sure of what we post and if we follow something posted... follow it to a "T" and be absolutely sure what we did was right.
If we're not sure, then stop where we're at and make sure.
I said it " It's a controversial opinion" and I personally try to ERR ON THE SIDE OF CAUTION for the most part.

Right-wrong or indifferent, It's how I feel sometimes reading the odd posts.
Lil Dog. You're absolutely right. Modifications have been made since fire was invented. I thought the same thing as you about that.
The reason why manufacturers VOID ALL WARRANTY when you modify any portion of their product, is that they don't want the liability falling on them. It's not the fact of the small change spent to fix your vehicle. It's the large costs associated with lawsuits.

Maybe it's just my subtle way of saying "BE CAREFUL"

 

Well all the fear of liability has now made me less senstive. The way it goes now you can be sued for anything, so why bother worrying about it..

Mod on boys!!! Remember what BOMB stands for:
Better
Off
Modified
Baby.

The factory was too cheap to do it right, so we have to.

 

Well you can all relax, my ECM is fine. As was stated above you need a TPS signal to run the cruise control. I picked up the correct potentiometer today(single turn, 2.5K), removed the guts from my TPS and installed the new one into it. Cost $20 and works ok so far. It is installed on the pump so my OD shifts still react to changes in throttle. Regular shifts driving upshift is around 50MPH and WOT upshift is about 65MPH. Going to run it for a while more and if it its ok I'll give a more through descripition. If it blows up your truck good luck suing me, I live in Canada, we are not quite so trigger happy with the lawyers here.

Still checking on the hard starting issue, may have slipped the timing a bit. Going to have a friend check it tommorrow.

Thanks for the tips.

 

cLAYH

Maybe check out the wiring to the KSB. I know mine would get loose once and while and make starting a little more intenstive. If the timing is off, you would notice alot more smoke at cold startup.

Good work on the potentiometer. There are alot of good quality parts at the electronics stores in Calgary that should outlast the stock stuff.

(BTW sorry to on the thread )

 

Rammer, I am not a lawyer, but back when I was heavily involved in Jeeps( Charter Pres of Flat-Landers Jeep Club, two Rubicons and countless trails) I learned that when you modify a vehicle, you are personably responsible for any problems as a result.

Just as if when you change a tire, if it were to come off and injure someone, the tire maufacturor isnt liable, nor is the vehicle manufactoror.
You are responsible for what you do. At least that is what case law going back to the 70"s here in KS says. It is part of the tort laws here. We had the same concerns when we started holding clinics on how to BOMB jeeps for off-roading and sought the advise of a lawyer who did tort claim suits.
I would think the same would apply here.
I wouldn't dream of trying to do halfthe stuff I have heard about here, 'cause I dont know my way around a deisel well enough... my jeep, well there was very little on it left undisturbed...
Most of the truck and vehicle magazines would be out of bussiness if they were liable for everyone who tryed a mod they describe and it didnt work out.
We are each responsible to know our limitations and if we exceded them, well its on us...

 

Getting a little paranoid in here. None of this is "forced" on anyone. They can surf a different site, or turn off their computer, or throw away their latest issue of TDR, or turn off the TV. Its all about choice. I choose to be my own warranty station when I modify my truck. I choose to read this site and the information/advice presented. There are those that choose to place blame on others when something doesn't go their way. Its too bad, but I'm not going to let them scare me into changing my behavior.