wait to start temp - again

[jaynes]

Hey there! It's been almost a year since I've posted a topic. . . wow. Anyway, I read a post recently about the preheating temps in the early Cummins ('89-'91) and Paul Herioux stated that there was a call out on the '89 rams that the controller didn't work right or something and the truck wouldn't preheat like it should. Correct me if I'm wrong, please. But I notice that on the 92 and 93 Rams, the WTS light comes on evn if it's 90 degrees outside, only for a second or so. I have an early '91 and it's starting to get cold out now, and even when it's 43 degrees (i keep a record of how cold it is) the grid heaters don't cycle and it doesn't like to run very well. The only time they come on, or I even see my WTS light is when it gets into the mid to low 30's. Is this right? I replaced my intake temp sensor not to long ago to see if it might correct the problem, to no avail. Is the controller wrong? Should the light come on all the time no matter how hot it is? Or is there something else wrong. I just notice things. And I notice my truck not wanting to run well in cooler weather . Thanks guys, I hope someone can give me an answer!



jaynes

 

[BushWakr - RIP]

I think that most all of these "lights" do a "diagnostic" when you go 'key-on'. Then they go out, which is normal.

There is no way that you should not see the WTS light when temps are as low as you say.

From 18*F - 59*F that light should come on for roughly 10 seconds indicating the pre-heaters are cycling.

You have a malfunction somewere.

As you know the 'charge air temp sensor' is the one closest to the intake 'horn' (my word). If you have changed that then maybe the recall is still an issue.

Check your wiring again, use electrical contact cleaner (not brake cleaner) to degrease the two connections, blow it dry and apply dielectric grease to the socket and reconnect it.

Failing that, you may have a faulty heater block. Since I really suck with electrical stuff I'll defer to someone else on how to test the heater/element(s). Maybe visually you can see a broken element if you remove the intake horn and just look at it.



I know this sounds kinda "wussy" but I plug in when temps drop below 10*C. I get a nice startup, way less smoke and and I'm on the road in less than 3 minutes that way. Plust the neighbours don't snivle as much too. .



If you need more help, let me know and I'll dig out the manual for you and do some reading... no problem. .



bob.

 

[jaynes]

diagnostics and recalls

Hey there Bushwakr!



Nice to be back on TDR talking with the diesel heads again. Yeah, I know there is no way I shouldn't be seeing that light at 59 or below. Something is funny. As for the diagnostics, the WTS light doesn't even come on in the "on" posistion (of the ignition) like the '92's and up. Infact, the only thing that comes on for a light check are the brake lamps and the oil lamp. I thought that the WTS was supposed to come on and then off for a light check when the key is turned on. It comes on while cranking though. Now you mentioned something about a recall. What recall, exactly, and I will try those things you mentioned. I have injectors to install sometime very soon (scared! Its my first time! ). If you have any other ideas about my WTS problem, that would be awesome. I really suck with electrical stuff too! Thanks man! Keep it coming!



jaynes

 

[BushWakr - RIP]

I thought you mentioned a recall when you said "... there was a call out... . " I took that to mean a recall.

Sorry if I misunderstood.

BTW, I've added a couple new 'gallery's to my readers rigs section. One covers the VE pump, and the other covers the TPS.

Take a look they are called "VE Gallery" and TPS Gallery".



Bob.

 

[farmall]

I have mentioned this fix before. The computer on my 92 went out and it caused my alternator to charge at max output, my speedo quit, cruise quit, and the Intake heater would not work. It got to the point last winter I could barely get it started below 10 degrees after sitting all day at work. So I broke down and bought a new computer. I installed it, about a 15 minute job. And low and behold everything started working including the intake heater. Not saying this is your problem, but the computer does control all of that and turn the relays on and off. Mine would also not light up until you cranked the motor, then would go out as soon as you let off the key. The stealer wanted almost $800 for a new computer. I got one at Autozone for around a $170 with a warranty. If you do order the comuter you will need the numbers off your old one as there are I think 3 different ones that will fit. Bill

 

[BCaldwell]

jaynes, our ctd's are the same vintageand my wts light comes on when the key is rolled through the run position to start the truck (just a flash with the water in fuel light). went out just now to confirm this approximatly 10:15 am wet coast time, 10 degrees celsi d heaters cycled before the wts light went out. bill

 

[jaynes]

So you're saying ...

Hey there sorry for the late reply! I'm alittle confused. Does it sound like my computer is working properly or not? Or does it sound like loose connections. I checked all my connections yesterday and everything seems to be fine. It was 48 Degrees this morning, and it coughed it spat white smoke for about 30 seconds before it started running right, oh and no preheat either! 59 Deg. or below? Yeah right, not my truck! Should I look into buying a new computer? Thanks for all the info, you guys are awesome.



Jaynes

 

[farmall]

I would say start at the relays and make sure you have power there when the key is on. I stress that you check the small lugs with the push on caps and not the large ones with the rubber covers. If you have current there I would say it is not your computer, but you cannot rule it out. It could possibly be that they are burnt out and are not working. I think you said you replaced the sensor and cleaned all the connections. If not make sure all the connections are clean and put dielectirc grease on them. Have you looked in to see if the heater grid looks good? I hate to tell you to try the computer as it is a expensive part to guess with. But all your problems and symptoms are exactly as mine were when my computer went dead. Hope this helps some. Bill

 

[jaynes]

Thanks farmall!

Thanks for the info!



I just was wondering because my light never came on when I turned the key to run (even as a bulb check like everyother diesel truck i know!). So I was curious cause I thought I should see it everytime I turn the key to run, even if it is just a bulb check, and not just when I crank the engine over. Also you mentioned when your computer went out it caused your alternator to do some funky stuff. I have a problem with fluctuating lights, not knowing if it's my alternator or not. But my head lights and dash lights and dome light flutter at a constant rate consistant with engine RPM's (try to imagine your engine idling and the head lights and other lights fluttering at that beat). Is that the alternator doing that? Could that be caused by a bad computer? Sorry to keep this post going, but these are questions that I have been wondering for some time! Thanks!



jaynes

 

[Lil' Dog]

89 - 91. 5 trucks don't have the computer the 91. 5 to 93 have that controls the charge circuit or the Pre-heat stuff. The alternator on the early trucks ( I had and 89) is controlled by a voltage regulator mounted on the firewall just above cylinder #6. They run about $10 and was changing about 1 every 14 months to get rid of that flutter you talk about. I even changed the alternator but it didn't help. The regulators are cheap for a reason. . LOL...



As for the pre heat, my 89 did have a lot lower temperature for pre-heating than my 93 does. But I found having the timing setup and the new injectors to help out alot in the starting. Actually my 89 started better than this 93 does with half the mileage. . LOL. .



I would check the connection to the WTS computer in the dash behind the CUMMINS consol and check the bulbs. After that I would use a test lite to see if you are firing the pre-heaters.



Good luck



J-eh

 

[jaynes]

Cool

Thanks Lil' Dog,



I knew that the early '91's didn't have the ssame computer the 91. 5's and up do. I don't know how those computers differ from the one I have. I have to pull the dash to replace some gauge lights, so I'll give that computer for the WTS a check and see. I have new injectors to put in the truck, they are sitting in my closet waiting for the right tools. As for that voltage regulator, I'll replace that too. Thanks for the help, and if anyone else can offer anymore suggestions, I'll be more than happy to read those too! Thanks a million!



jaynes

 

[farmall]

Sorry about the bad info. I assumed the 91's had the computer also and all they changed was the Inter-Cooler. Bill

 

[jaynes]

no problem Bill, nothing to be sorry about. You know more than I do!



jaynes

 

[Lil' Dog]

Originally posted by farmall

Sorry about the bad info. I assumed the 91's had the computer also and all they changed was the Inter-Cooler. Bill

Well its not your fault for sure. . Dodge pulled a fast one and if you have the earlier 91's you got the non-intercooled version without the computer system. . After 91. 5 they offered the intercooler version Don't ask me why. .



Same with The 98's. . Early 98 quad cab P7100 12 valve, late 98 24V ISB. Then Early ETH in 2001, first half was with rear drums. After 2001. 5, you got rear disks. . Go figure. .



J-eh

 

[jaynes]

computer

Leave it to Dodge to pull fast ones . Is this "new" computer in the 91. 5's compatible with the early '91's? I mean, is it possible to install one of those in, say, my truck versus the computer I have in there now? Just curious. Sorry, this is all very interesting to me.



jaynes