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1999 ECU / Wait To Start Light

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47rh weird reverse problem...

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almost 2 yrs later... ...

You wouldn't happen to have another ECM laying around would you? I just bought another 99' auto with only 250,000 miles on it and sure enough it needs an ECM too. As a test I installed the ECM out of my manual 99 in the new to me 99 auto, sure enough it's right as rain. I'd like to keep the manual truck for pushing snow so now I'm on the hunt for another ECM.


If anyone knows of a reputable shop that's repairing owner's ECM's I'd really like to hear from you. I've been calling around but everyone I've spoken to doesn't or won't work on ECM's for 2nd gen diesels.


Thanks
Mike

BTW my poor old 99 manual now has 465,000 miles on it.
 
Mike,



There are a few used ones for sale on eBay. Not exactly inexpensive mind you, but much less than buying a refurbished one from Dodge or Cummins.



John L.
 
Thanks John, I've seen those as well but to be honest I just don't trust the sellers. Unless the seller can say for sure that the ECM came off of their truck and was in good working order It's not worth it. While I don't mind a fair price for one, I can't afford to buy them over and over again hoping to get a good one.

Not everyone is as trustworthy as a TDR member ya know.

Mike
 
Thanks John, I've seen those as well but to be honest I just don't trust the sellers.
Mike,



Before you rule out those eBay sellers, at least be sure and consider the amount and level of their feedback. If they're well established, have good consistent feedback, and the purchase will be backed by eBay's buyer protection plan, then the overall risk to you is low.



I've purchased a couple ECM's on eBay and (thankfully) they've both worked fine.



John L.
 
I decided to take your suggestion and bought one off ebay. The guy had 5 of them and a good rating so I think I'll be alright. If this one is in good working order I may have to buy a couple for spares.

cheers
 
To be honest Mike, that's what I did... over the years I bought a couple of them as emergency spares.



I intend to keep my truck indefinitely and these ECM's aren't going to get any more plentiful or cheaper.



I hope you get a good one.



John L.
 
Can I ask what you gave for an ecm off of ebay? Was it for an identical truck (same year/trans configuration)? If not, I believe it has to be flashed by a dealer correct?
 
The ECM was $550 & comes with a 30 day warranty. He had 5 of them listed. 98. 5 thru 2001 all take the same ECM and are all interchangeable between manual and auto. I know this because just last week I took the ECM out of my 99 manual and installed it in my 99 auto truck and every thing works. I'm pretty sure I picked up a%2
 
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To be honest Mike, that's what I did... over the years I bought a couple of them as emergency spares.

I intend to keep my truck indefinitely and these ECM's aren't going to get any more plentiful or cheaper.

I hope you get a good one.

John L.


No such luck on the first Ebay ECM, it was a dud. Fortunately the Seller is making right by shipping out another one once he receives this one back. Another update will follow in a week or so.

cheers

Mike
 
John,

The first tip off was the way in which the lift pump fired and ran at key on. The lift pump should only run for 1-2 seconds at key on as long as the fuel system pressurizes. With the replacement ECM the lift pump fired off at key on but never shut off. The WTS light also never illuminated which is another common mode of ECM failure, at least for the two I've had go bad over the past 14 yrs I've ownership of my manual truck. It did start after 3 tries but I only let it idle for 10-20 seconds because it was running so poorly. As soon as re-installed my ECM (5 spd ecm in my auto) everything worked as it should and the engine runs perfectly.

I had my doubts when I opened the box and saw that all the screws on the ECM were rusted and the 50 pin connector was covered in what looked like a layer of mud. It took me 20 min just to clean the pins. After a few txt messages with the seller I learned that he has lots of returned units because many of the yards he buys the units from just don't test them at all. When he buys them they don't come with any warranty at all but he warranties them for 30 days. My guess is that the warranty period is mandated by ebay since he's an "ebay seller" Basically he takes a hosing every time he sells a bad unit unless he can flip if for a core to a rebuilder. According to him a dead ECM is worth about 200 bucks just a core.


Mike

Mike,

Just curious...

What did the dud ECM do (or not do)?

Thanks,

John L.
 
Mike,



I vaguely recall some years ago a TDR member reported odd behavior similar to what you're describing when swapping ECM's of different engine/transmission configurations. When I get time, I'll do some searching and see if I can find some of those posts.



John L.
 
Mike,

I vaguely recall some years ago a TDR member reported odd behavior similar to what you're describing when swapping ECM's of different engine/transmission configurations. When I get time, I'll do some searching and see if I can find some of those posts.

John L.

I've swapped ECM's back and forth between my manual transmission and automatic transmission trucks without issue several times now. The only diff is the auto truck runs a bit stronger when it's running on the Manual's ECM. I believe all 98. 5-2002 should be interchangeable meaning without flashing for either manual or auto transmission.

The lift pump running oddly as well as the wait to start light having a very long delay before firing have been the mode of failure on the last two ECM's I've had installed, one in each truck.
 
You would think there would at least be a difference in the HO units? There is a difference in the VP's between a HO and a non HO model, found that out the hard way several years ago when I helped a friend change a pump out he got out of a salvage yard.
 
Mike,



I would've loved to know the part numbers for the config. files of both your ECM's and the one you received from the eBay seller so we could compare things. Unless the Dodge stickers are still on the ECM's (they do wear off), I think you'd need a DRBIII to find out.



Just to be safe, I made sure the ECM's I bought off eBay were identical to the original on my truck's engine.



John L.
 
Both ECM's I have here on the bench are missing their Cummins data plates but the DC decals are mostly intact.

These numbers are from the smaller decal with barcodes on the ECM out of my 99 manual. I'm the original owner so I know it's the OEM ECM.
P3942336
5102119253
T0409

Same decal on the Ebay ECM. There's tamper prove tape on the 50 pin connector which I believe DC didn't start using until 2000 but I'm not 100% about that.
P3946242
1802085596
T1460


The ECM that is currently in my automatic is was until a few weeks ago installed in my manual truck. The numbers on that one are different as are the numbers on the automatic ECM that is currently installed in my manual truck. I checked the part numbers when I was swapping things around but didn't bother to write them down. I do know from talking to the previous owner of the automatic truck that the ECM has never been replaced so I'm assuming that it's OEM.

I'm interested to see what you can dig up
 
I looked at the picture of where the connector is supposed to be, and I don't seem to have that one. At least it's not in the same place. Truck in question is a '98. 5 3500 with 5 speed manual NV4500. I didn't see anything that even looked like it.
On another note, when I have a fuel pressure gauge hooked up to the ports on top of the fuel filter, and turn key off, the fuel pressure drops to zero in just a few seconds. Is this normal? If truck is running and I shut it off, then try to start it within a few seconds (some fuel pressure still showing on gauge) it'll still start just fine.
 
MChrist, that connector should be right where the picture show it, at least that's were it is on both of my 99's. You may have to move the weather stripping out of the way to get a good look at it but I'm relatively confident It's there.
 
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