1997 2.4 rough idle/rich/black smoke

Thanks for the info! He doesn’t seem to have any in stock of the ecm I need but I sent him a message. If anything I’ll have to order from flagship one for $450

 

I’m thinking a new ecm will at least solve my scanner not connecting to truck issue, considering the obd2 port is functioning properly to the best of my knowledge. Then from there I can diagnose a lot better. I’m just waiting on module madness to respond to see if I can get a cheaper deal than the flagship one. Flagship one is $450, that cost more than what I paid for the truck LOL

 

(1) 2rz-fe ecm 96 - Bing

Pretty sure the 3rz ecm's work too....just has to be same-ish year and tranny...

if you have part# off old ecm ... which is printed on it..... its easy to find them on ebay.....bought a backup for my 98 2rz for like $50 on ebay.....

 

So I ended up ordering a used one from eBay, for $350 shipped. Same exact part number and same year. Says returns accepted as long as I don’t open or damage the unit. If it doesn’t fix my truck or at least get it to connect to a scanner I can always return it ‍♂️

 

Maybe ask module madness to repair yours?

 

That could be an option too so if this new one works, I could have a spare. But he hasn’t responded to my message on eBay yet.

 

Well well well. I have some great news!

The new used ecm came in this morning and I plugged her in. Immediately before I even started the truck I plugged in the scanner and it connected! But it is telling me there’s no codes. I started up the truck and it screamed like I’ve never heard it before. No rough idle! There is a high idle though but that’s because I have to reposition the TPS. Read fuel trims and all are around 0.00 give or take. No smoke at idle either! Gonna tweak with the TPS to get it just right and go for test drive and report back.

but yup just like Wurmwood, swapping out ecm did the trick!

 

That's great!

 

Hell yeah!

 

So it looks like my short fuel trim is between -7 to -10. Long fuel trim is 0.00. My idle is pretty high even with throttle set to its lowest point (barely letting the throttle blade open so it doesn’t completely cut off air coming in. My rpm was like 1200-1400. With the TPS turned completely clockwise (facing the truck) it brought my idle down to 900-1000. Which is a lot better than 1200-1400. What are you guys idling at? Or am I missing something?

Also, no check engine light!

 

So truck drives GREAT! I’ve never experienced it running the way it is now. So this is how it’s supposed to drive lmao. I’m thinking the 900-1000rpm idle will be fine. Well hopefully this thread will help out some people in the future. With rough idle/poor acceleration & scanner not connecting, definitely do not rule out ecm!!

 

Also, the truck’s ac compressor used to not work. I noticed when I put direct power to the ac compressor plug that it will kick on the compressor clutch and I was able to fill it with the right amount of frion. But without direct power from the battery, the compressor clutch doesn’t engage from the dash controls.

but with the new ecm, I turned on the ac just to see, and the ac compressor clutch engages’
! I have ice cold ac now
With ac on, my idle went down to 750-800rpm so I’m pretty content with the idle with or without ac on.

 

Your high idle is probably due to the throttle body and butterfly valve being worn out like mine is. If you take the throttle body off and twist the butterfly valve closed while holding it up to some light, there should be no visible light coming in around the valve. If there is, that is why its idling high. Mine has just a tiny 1 or 2mm gap on about 1/2 of the butterfly valve and its enough to make it idle high. Other wise GRATS though! It definitely is like a totally different truck after.

 

Or give the ECM a few days to "learn" the new sensors it's attached to.

It takes a few days and 50-100 miles after a computer reset for everything to settle in and all the tests to run.

 

Thanks man

 

Yeah I noticed today that from cold start it is idling around 700-800rpm but warmed up it’ll go back to 900-1000rpm. I’m satisfied with it overall. I don’t think I’m going to change anything unless a code comes up