Could a incorrect ecu cause surging idle?
03-06-2006, 05:00 AM
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Could a incorrect ecu cause surging idle?
When i first bought my car i was told the idle surged beacuse of the ecu. I was told they put a p28 in it and it stopped surging. Anyone heard of this problem? Is this a real solution to my surging idle or was the guy an idiot??? Anyone heard of this? Thanks.
Mike
Mike
03-06-2006, 10:16 AM
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I recently swapped over my JDM B18C into my other car it started having low idle issues which it never did before.
My JDM p73 ecu doesn't surge, but once the car is warm up the idle starts dropping to like 200-300 rpms and then it kicks or surges back up to 800rpm and does that over and over. Funny thing is it doesn't do that every time.
When I put the P28 chipped ecu in it doesn't do that at all... im like WTF? The only problems I have with the P28 ecu is hard startup on cold days. Once it warms up it has no starting problems or idle problems. It doesn't have either problem on a non cold day.
I don't know if that P28 ecu is gonna solve your problem...
My JDM p73 ecu doesn't surge, but once the car is warm up the idle starts dropping to like 200-300 rpms and then it kicks or surges back up to 800rpm and does that over and over. Funny thing is it doesn't do that every time.
When I put the P28 chipped ecu in it doesn't do that at all... im like WTF? The only problems I have with the P28 ecu is hard startup on cold days. Once it warms up it has no starting problems or idle problems. It doesn't have either problem on a non cold day.
I don't know if that P28 ecu is gonna solve your problem...
03-06-2006, 10:35 AM
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Re: (entityzero)
I have a b16 and I have the same problem but I have both ecu's and they r the same. let me know if u find the problem. BTW someone told me to pull out the ecu fuse underneith the hood n keep it out for 20 mins because they said pulling the pos. n neg. doesnt reset the ecu. Ive been told different though so I dont know
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03-06-2006, 11:19 AM
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Re: (2lua)
i dont have any vaccum leaks as i can find. ive cleaned my iacv and havnt checked my fitv yet. i think my p30 ecu is a ghetto chipped pos...
Mike
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03-06-2006, 12:50 PM
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Re: (mikeunreal2)
is your ecu actually bolted down or is it just layin in the floor? if my ecu(p28 or my p30)isnt bolted down to ground the outside of the case my idle surges. any hope this helps.
03-06-2006, 03:01 PM
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Re: (5THGENSI)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 5THGENSI »</TD></TR><TR><TD CLASS="quote">is your ecu actually bolted down or is it just layin in the floor? if my ecu(p28 or my p30)isnt bolted down to ground the outside of the case my idle surges. any hope this helps.</TD></TR></TABLE>Is this true? anyone know
03-06-2006, 03:34 PM
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Re: (hondachris1994)
I had the same prob but it was on a stock D15B7 and on my JDM D15B after the swap. I used the stock mani off the B7. I took all that I could off the Intake mani. and cleaned it out and made sure everything was tightened down. Just a suggestion, but try it.
And I dont think the ECU being bolted or unbolted will make a difference. I had my P28 on the floor for a week after my D15B swap and it didnt make a difference.
And I dont think the ECU being bolted or unbolted will make a difference. I had my P28 on the floor for a week after my D15B swap and it didnt make a difference.
03-06-2006, 03:45 PM
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Re: (Sandmaggot)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sandmaggot »</TD></TR><TR><TD CLASS="quote">
And I dont think the ECU being bolted or unbolted will make a difference. I had my P28 on the floor for a week after my D15B swap and it didnt make a difference.</TD></TR></TABLE>thats what I thought 2
And I dont think the ECU being bolted or unbolted will make a difference. I had my P28 on the floor for a week after my D15B swap and it didnt make a difference.</TD></TR></TABLE>thats what I thought 2
03-08-2006, 05:49 PM
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Re: (importkidd)
i cant find a leak in my vaccum lines, everyone keeps saying check those but i dont know where to look or what im looking for, or how to look
03-08-2006, 07:04 PM
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Re: (mikeunreal2)
I had the same problem. My IACV and FITV were bypassed (JDM B18C w/P72 ECU), once those were connected to the coolant system, the idle was fine.
I have an Eric's racing P28 that's not hooked up, I'm thinking the previous owner was using this and it idled fine and when he put the P72 back in it got FUBAR'd. If you need pictures of how to hookup the IACV and FITV I can post some.
I have an Eric's racing P28 that's not hooked up, I'm thinking the previous owner was using this and it idled fine and when he put the P72 back in it got FUBAR'd. If you need pictures of how to hookup the IACV and FITV I can post some.
03-09-2006, 07:08 AM
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Re: (jklobo)
I had the same problem and didnt find any vacuum leaks heres what I did.....take a small piese of cardboard and loosen ur IACV (loosen bolts just a lil not all the way off) take the piece of cardboard and ccover the screen on the IACV and then tighten it back (with cardboard covering screen) then start ur car and it should idle fine.. If it still idles irratically u have a vacuum leak.If not u mught have to adjust the idle but this will work I just did it last nt. But there is 1 catch when u start ur car n the morning u have to hold the gas till it warms up then it will b fine
03-09-2006, 02:46 PM
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Re: (mikeunreal2)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mikeunreal2 »</TD></TR><TR><TD CLASS="quote">how can i tell if my crap is bypassed?</TD></TR></TABLE>there wouldnt b any coolant line goin to them. Try what I said my idle did that for a month and drove me crazy
03-09-2006, 08:06 PM
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Re: (importkidd)
I am having the same idle problem. I have a stock 95 civic, 5 speed. I am not sure where to check for the vacuum lines, fitv, and iavc. In addition, I have a weird surging problem when driving. When I step on it, roughly 2000 - 3000 rpm, it gives a surge. It doesn't happen all the time. Could the two problems be related? Any suggestions much appreciated.
03-09-2006, 08:33 PM
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Re: (sp0097)
man i had the same ? i think it can be the ecu cause my car was fine before i put a chipped p28. when i put the p28 in it started surging. people dont like to read the initial question they see surging idle and say oh its a vacuum leak or the iacv sometimes it could be the ecu. just in case take carb cleaner to your iacv to clean it out. you know just for the hell of it so you know its not the problem . make sure it fully dry's out 
03-09-2006, 09:16 PM
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Re: (e gee two)
Cleaning the IACV sounds like the best first step to take, from reading all of the different posts on this topic. That way you don't have to go any further than that.
I think you may be right about the ECU thing and here's why I think so, someone correct me. The ECU program may bypass the IACV and set the idle speed so if you go back to the stock ECU it'll start surging at idle (that's the way my car was when I got it. It had the stock ECU but the guy gave me a chipped P28 that he used previously). That could explain why my IACV and FITV were both bypassed.
Where in so cal are you e gee two?
I think you may be right about the ECU thing and here's why I think so, someone correct me. The ECU program may bypass the IACV and set the idle speed so if you go back to the stock ECU it'll start surging at idle (that's the way my car was when I got it. It had the stock ECU but the guy gave me a chipped P28 that he used previously). That could explain why my IACV and FITV were both bypassed.
Where in so cal are you e gee two?