DodgeIntrepid.Net Forums banner

1 - 17 of 17 Posts

·
Premium Member
97 Dodge Intrepid ES 3.5L First gen
Joined
·
21 Posts
Discussion Starter · #1 ·
I've heard that replacing the ECU with a PROGRAMMED replacement resolves inherent overheating issues. Has anyone heard the same or anything similar?

I found a decent, programmed (important to make sure it's been done) replacement for under $100 on Amazon. Shouldn't be too hard to swap out, Right?

Question out of all of this is twofold.
1) Anyone care to bunk/debunk the theory?
2) Anyone know if this is a tricky swap? Seems to me It's on the driver side under hood behind the battery compartment...

Hey. I just work here.
Love me a Trep.

Tim
 

Attachments

·
Woober Goobers!
Joined
·
51,209 Posts
Where did you hear this from?
 

·
Registered
Joined
·
47 Posts
My Concorde has overheated twice in the 10+ years of ownership. Each time was because the impeller on the water pump cracked in half. So if you're having overheat issues, I'd check the pump first. Annoying on the 3.5L since its hidden behind the timing belt cover.
 

·
Premium Member
97 Dodge Intrepid ES 3.5L First gen
Joined
·
21 Posts
Discussion Starter · #4 ·
Where did you hear this from?
If I remembered specifically, I would cite it. I've got enough head injuries that it'll take awhile before I can get back to you on that one.

I must say, too, great way of saying"Never heard of it". 😉 Kudos!

Well, as soon as this Virginia rain ends, reckon I'll get in there and see what happens.

I mean... Got this ECU. 🙌

Thanks
 

·
Registered
Joined
·
4,355 Posts
No such thing as reprogrammed ecu and coolant temps.,


Engines are just a PITA to bleed properly. I found through the years I would fill the system up with nose and pass side lifted through the top rad hose until coolant came out the T-stat housing. Reconnect hose. I would then open the T-stat bleeder and slowly fill up until reservoir was nearly full.

Here is my trick, I would tighten bleeder, then remove the overflow hose and attach a hand vac pump to that nipple. Place my hand over the Lid and draw a vacuum until hoses start to collapse. See a lot of air coming through tank (bubbles) I would then lift my hand allowing suction to draw back in fluid. I would repeat this keeping tank full until no more bubble came out.

This has worked several times much better than letting it bleed while running. And works on my 2011 Charger Pursuit as well.
 

·
Registered
Joined
·
4,355 Posts
Also,

PCM is Passenger side under airbox

TCM is beside Battery on Driver side.

BCM is passenger side behind glovebox in the corner.
 

·
Registered
Joined
·
2 Posts
There is a lot of things to be look at before you go and replace an ecu first of all make sure your fans are working correctly if so then check your ecu with a professional scanner the $40 will not work if everything is ok then check your radiator for leaks and clogged up passages, check thermostat, and water pump, the computer will be the last thing you want to replace and make sure you bleed out the system properly.
 

·
Registered
Joined
·
161 Posts
My trep is a 2nd gen, but what I did to resolve overheating should apply to yours as well if bleeding does not work:

.
 

·
Premium Member
Joined
·
17,492 Posts
Not that this will affect anything that has been said, just pointing out that the t-stat of 1st gen. is traditionally located just upstream of upper radiator hose. On 2nd gen., it's located at downstream end of lower radiator hose.
 

·
Registered
Joined
·
2 Posts
My trep is a 2nd gen, but what I did to resolve overheating should apply to yours as well if bleeding does not work:

.
Then your water pump is probably shot , it doesn’t have to leak to tell is bad but if the impeller got loose Inside you won’t be able to tell just check the electrical first before you decide to to do a timing job as well, they are not that hard to work on I have done many of them from 2.7 - 3.5 they are pretty easy compared to other cars I fixed before . Please use good quality parts don’t use eBay China cheap parts try to get Dayco, Gates , Continental parts or preferably OEM MOPAR , as I mentioned I do have pretty extensive experience working on cars and I know for fact the cheap stuff can become extremely expensive, ask how do I know and why I decline customers with eBay parts . And since you’re there change your radiator is worth it .
 

·
Registered
Joined
·
56 Posts
Genuine Mopar is not immune from failure. I had a brand new Mopar pump impeller slip on the shaft, within a day or two of installation. I can't believe they don't pin those impellers.
 

·
Premium Member
97 Dodge Intrepid ES 3.5L First gen
Joined
·
21 Posts
Discussion Starter · #12 ·
My Concorde has overheated twice in the 10+ years of ownership. Each time was because the impeller on the water pump cracked in half. So if you're having overheat issues, I'd check the pump first. Annoying on the 3.5L since its hidden behind the timing belt cover.
Thanks. I did replace the water pump recently.

And I'm on my 6th coolant reservoir replacement.

I have installed a kit to keep the fan running on the hi end, but not only did it fail to keep the Trep from overheating, it ran the battery down (don't get me started on the Dead Trep battery saga).

I've replaced the T Stat with a 180° threshold, and despite burping the heck outta her many times, that didn't help either. And any loyal Intrepid owner knows that once that needle makes it past the halfway mark, it's not a question of WILL it overheat, it's about WHEN. it overheats... Answer: Shut off your engine and stop wasting time thinking. ⌛

If replaced the PCM, the MAP website, the Temperature Control Sensor, the plugs, the wires,...
The filter was modified for a cone filter, and I've installed a functioning hood air scoop, college with an intake fan from a PC desktop unit.

Wanna guess?

Still overheating.

SO, friends... Why wouldn't it make sense to TRY replacing the ECM at this point?

I've replaced everything else, and modified other things, but to no avail...

Well kids, I think I'll try to pre-programmed ECM replacement idea I started out with, and pray.

DidI mention also I got a new radiator and fans?

And changed the coil packs?

And flushed the radiator twice, once professionally, wasting my money yet again...

Other than some major engine components, I've replaced nearly every moving part in this baby.

Now really, folks.... Do I really have much of a choice now?

In 10 years I've yet to meet a competent Intrepid mechanic, so I'm in this alone for the long haul.

And y'all are some pretty smart kids, so thought I'd throw it at the wall and see what sticks, and what falls on the floor.

Thanks.

Tim
 

·
Premium Member
Joined
·
17,492 Posts
This won't help you, and may even irritate you, but it reminds me of an old joke:

I was talking to an old man the other day, and he showed me an axe. He said "This is the best axe I've ever owned. Had it 40 years. I've replaced the handle twice and the head once, but still the best axe I've ever owned."

:cheers:
 

·
Registered
Joined
·
618 Posts
after all those parts, it would have been cheaper to get a vacuum filler for your coolant.
have you flushed the block?
a new rad precludes flushing the whole system.
late timing can overheat an engine.
tried premium fuel?
 

·
Registered
Joined
·
47 Posts
And I'm on my 6th coolant reservoir replacement.
That's insane. There's no reason why you should be replacing those that often, unless you're using the cheap Dorman aftermarket crap. I still have my original factory reservoir - only thing I replaced was the cap. A $7 part at the local Chrysler dealership.

With all of the overheating your Trep has gone through, I'd say at this point the block and the heads are compromised. Maybe cheaper to look for another healthy engine or another Trep and cut your losses.
 

·
Premium Member
Joined
·
17,492 Posts
That's insane. There's no reason why you should be replacing those that often, unless you're using the cheap Dorman aftermarket crap. I still have my original factory reservoir - only thing I replaced was the cap. A $7 part at the local Chrysler dealership.

With all of the overheating your Trep has gone through, I'd say at this point the block and the heads are compromised. Maybe cheaper to look for another healthy engine or another Trep and cut your losses.
I second the comment on the Dorman reservoirs (probably all of the aftermarket reservoirs are from the same source). I don't know if OEM ones are still available or not - maybe can get them on ebay? I know ones for 2nd gen have been available on ebay. Go with OEM if at all if possible on the coolant reservoirs.
 

·
Dain bramaged
Joined
·
7,259 Posts
Get an exhaust gas test done on your coolant system. If you've gone through all of this and still have issues it could be a bad head gasket or a crack into a coolant passage.
 
1 - 17 of 17 Posts
Top