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New ECU and still have issues

 
Old 05-21-17, 09:11 AM
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TREYFIGGS
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Default New ECU and still have issues

Well I have replaced the ECU and from first thought it worked. however, my wife, bless her heart really doesn't pay much attention. I drove it yesterday for a good amount. it is still running really rough. What I have noticed is it really lags when you give it hard gas. lay down the finally reacts...slowly. Starting from stop you can really tell it also if I'm trying to get into the fast lane from slow lane. also when sitting at stop I can feel the motor surging, erratic rpms. Anybody have any ideas what this could be? thank you in advance. Thank you ,
Trey
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Old 05-21-17, 07:14 PM
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Yamae
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Was the replaced ECU had all recommended new capacitors and traces were not damaged?

I still don't understand fully what you have done.
You once wrote,

"I think I'm gonna have my original one rebuilt like you did yours".

and then at your next post, you wrote,

"Yes, I did".

So I thought you have replaced all capacitors. But you didn't write the details and I have no idea to comment.
If you are in a situation as follow, you need to replace all those QAS capacitors since those are 27 years old and mostly outdated.
"You used another ECU which still had original capacitors."
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Old 05-23-17, 11:26 AM
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What symptoms were you having before replacing the ECU?


Too often people replace/rebuild them without properly diagnosing what the actual root cause of their issue is.
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Old 05-28-17, 12:35 PM
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Originally Posted by Yamae View Post
Was the replaced ECU had all recommended new capacitors and traces were not damaged?

I still don't understand fully what you have done.
You once wrote,

"I think I'm gonna have my original one rebuilt like you did yours".

and then at your next post, you wrote,

"Yes, I did".

So I thought you have replaced all capacitors. But you didn't write the details and I have no idea to comment.
If you are in a situation as follow, you need to replace all those QAS capacitors since those are 27 years old and mostly outdated.
"You used another ECU which still had original capacitors."
Sorry I was so confusing, this is all foreign to me. I bought a new ecu and had a guy (certified electrician and a wicked solderer lol) put the caps on. That's why I I'm confused to what it could be now. Again I'm sorry if I don't make the most sense, I really mean to. Thank you.
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Old 05-28-17, 12:38 PM
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Originally Posted by PureDrifter View Post
What symptoms were you having before replacing the ECU?


Too often people replace/rebuild them without properly diagnosing what the actual root cause of their issue is.
Same thing as I said in the first comment on this thread, plus when at a stop/idle it has erratic rpms. Can feel it in the peddle when in drive at a stop. Occasionally it just dies, like i turned the car off. when I pull over and turn the key off I can start it right back up. Thank you
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Old 05-28-17, 07:46 PM
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iac...tps..air flow meter. rebuilding ecm's arent a fix all,pd is correct. i replaced my caps just so i wouldnt have to worry about it in the future (3 years ago) but i wasnt having any problems and bought the exact caps yamae is referring to.
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Old 05-30-17, 10:01 AM
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Have you narrowed it down to determine if its a misfire on all cylinders or one in particular? I'd start by removing spark plug and distributor covers. And when its acting up have some injsulated gloves, pull each spark plug wire at cap and see if it makes a difference. If all cylinders are hitting, I'd lean more towards an air fuel ratio problem, have you checked fuel pressure?
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Old 05-30-17, 11:15 AM
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I have not checked fuel pressure yet. Pretty much does it all the time so I'll check that probably tonight when I get home from work. And as far as fuel pressure, how do i check that and do you know off hand what it should be. Thank you.
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Old 05-30-17, 11:30 AM
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Originally Posted by TREYFIGGS View Post
I have not checked fuel pressure yet. Pretty much does it all the time so I'll check that probably tonight when I get home from work. And as far as fuel pressure, how do i check that and do you know off hand what it should be. Thank you.
I'm pretty new to the 1uz but if you dont have the tools on most fuel rails theres a little vale you can release fuel pressure with and if you have good fuel pressure should spray prettty well. Now again this is on like say a 360 magnum v8. I don't know if the 1uz has such a thing ,but it should.
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Old 06-01-17, 04:05 AM
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Originally Posted by shamanic View Post
I'm pretty new to the 1uz but if you dont have the tools on most fuel rails theres a little vale you can release fuel pressure with and if you have good fuel pressure should spray prettty well. Now again this is on like say a 360 magnum v8. I don't know if the 1uz has such a thing ,but it should.
thank you bro, I'll try that this weekend. All the help is GREATLY appreciated.

Trey
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