5th Generation Maxima (2000-2003) Learn more about the 5th Generation Maxima, including the VQ30DE-K and VQ35DE engines.

Changed IACV, still driving with toasted ECM

Thread Tools
 
Search this Thread
 
Old 08-19-2013, 01:14 PM
  #1  
Junior Member
Thread Starter
 
Stru's Avatar
 
Join Date: Jan 2013
Location: Branford, CT
Posts: 81
Changed IACV, still driving with toasted ECM

Now I'm going onto putting in a fresh ECM, but is the IACV I installed now crap too since I've been driving my car with the shorted ECM? I hear rumors that a crap ECM will destroy a IACV and TPS but I don't see how that is even possible since the mosfets that power the motors are just dead. Worse case scenario is that the motors aren't receiving signals from the ECM, correct?

Has anyone had experience with this? I'd like to hear from a trusted source.

Oh and when the issue first started, the diagnosis was a failed IAC motor, not the motor mounts. I've been driving with them unplugged as a precaution.
Stru is offline  
Old 08-23-2013, 09:12 AM
  #2  
Junior Member
Thread Starter
 
Stru's Avatar
 
Join Date: Jan 2013
Location: Branford, CT
Posts: 81
Still no reply on this? Nobody else has done this before?
Stru is offline  
Old 08-23-2013, 11:35 AM
  #3  
Senior Member
iTrader: (21)
 
EuroDriver's Avatar
 
Join Date: Aug 2011
Location: San Diego, CA
Posts: 1,284
If you're still driving your car, I seriously doubt the ECM is your problem. (I'm speaking out of experience here).

First of all, I hope you new IACV is OEM. If it's aftermarket (especially Autozone) it's about as good as you old, dead one. When I changed my IACV, I initially installed one from Autozone, which made my symptoms much worse. (Initially, I had no symptoms other than SES). After making fun of me, my wrench advised me that it's best to buy those types of parts from the dealer.

After installing an OEM IACV, my headaches and expenses continued, as I could not get the car running right (I had a surging idle between 600 -1600 RPM). Dealer told me it was a fried ECU after spending 2 days diagnosing it. Several folks advised me it was unlikely, so I did not replace the ECU. After visiting another handful of garages, one garage manually adjusted the idle at the throttle. After that, I performed the idle relearn procedure and the car has been fine since.

Unless you opened your ECU and confirmed the MOSFETs are burned, I would take that diagnosis with a grain of salt & keep looking.
EuroDriver is offline  
Old 08-24-2013, 06:41 AM
  #4  
Member
 
Pilm's Avatar
 
Join Date: Oct 2009
Location: FloriDUH
Posts: 187
Originally Posted by Stru
Now I'm going onto putting in a fresh ECM, but is the IACV I installed now crap too since I've been driving my car with the shorted ECM? I hear rumors that a crap ECM will destroy a IACV and TPS but I don't see how that is even possible since the mosfets that power the motors are just dead. Worse case scenario is that the motors aren't receiving signals from the ECM, correct?

Has anyone had experience with this? I'd like to hear from a trusted source.

Oh and when the issue first started, the diagnosis was a failed IAC motor, not the motor mounts. I've been driving with them unplugged as a precaution.
I say no but the only way to convince yourself the rumors are bogus is to take out the IACV and measure the 4 coils, 22 ohms each is good. See FSM EC-432 for pin numbers of coils, EC-436 step 8 for measurement.
Pilm is offline  
Old 09-18-2013, 05:04 AM
  #5  
Newbie - Just Registered
 
ihk777's Avatar
 
Join Date: Sep 2013
Posts: 8
Hi,
My 01 has been diagnosed as having fried ECU components. BUT it still runs wthout idle problems? Mind you that was just home from the auto elec.
The ECU has been removed and we have photos I have tried to have identified. One person says check electronic motor mounts.
My partner is going to disconnect them soon and see if we can
get away without replacing ecu and iac and tps and see how it goes.
ihk777 is offline  
Old 09-18-2013, 01:58 PM
  #6  
Senior Member
iTrader: (2)
 
DennisMik's Avatar
 
Join Date: Apr 2004
Location: Plano, TX
Posts: 10,649
Read this thread and you will probably get your answers. It is a long thread, but it had a lot of information.

http://forums.maxima.org/5th-generat...d-seconds.html

post # 5 explains what the chip does.
post # 27 has an ECU picture with a fried chip.
post # 29 has photos of the repair process.
post # 38 has photos of fuses being added to the ECU.
post # 70 states ecu repaired for $70 by autoecu.com
post # 78 states 2 places were the chip were bought.
post # 86 is another ECU repair place that charges $160.
post # 93 guy has a 2000 Infinity I30T & his ECU is slightly different.
post # 98 another guy with a 2000 Maxima has same ECU as infinity.
DennisMik is offline  
Old 09-18-2013, 10:32 PM
  #7  
Newbie - Just Registered
 
ihk777's Avatar
 
Join Date: Sep 2013
Posts: 8
Originally Posted by DennisMik
Read this thread and you will probably get your answers. It is a long thread, but it had a lot of information.

http://forums.maxima.org/5th-generat...d-seconds.html

post # 5 explains what the chip does.
post # 27 has an ECU picture with a fried chip.
post # 29 has photos of the repair process.
post # 38 has photos of fuses being added to the ECU.
post # 70 states ecu repaired for $70 by autoecu.com
post # 78 states 2 places were the chip were bought.
post # 86 is another ECU repair place that charges $160.
post # 93 guy has a 2000 Infinity I30T & his ECU is slightly different.
post # 98 another guy with a 2000 Maxima has same ECU as infinity.
Thank you very much for your info above. I am a very new noob? and don't understand which thread you are referencing?

Last edited by ihk777; 09-18-2013 at 10:34 PM. Reason: Sorry, figured it out- click on refernce. Thank you
ihk777 is offline  
Old 09-18-2013, 10:57 PM
  #8  
Newbie - Just Registered
 
ihk777's Avatar
 
Join Date: Sep 2013
Posts: 8
Thanks DennisMik

I checked out that thread. Some similarities definitely.

I am relying on the expertise on this great forum. I don't know anything about cars but my partner is a capable person under the hood of older car so I am hoping with the right advice he can get me going again. Car has been sitting for 3 months.
As I am new I am wondering can I post on that thread my own experience and photos for advice or should I do it on the thread for newbies?
Thanks
ihk777 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
tsi6001
5th Generation Maxima (2000-2003)
12
10-03-2022 10:23 PM
schmellyfart
All Motor
7
09-25-2015 04:47 PM
homeyclaus
Maximas for Sale / Wanted
1
09-03-2015 06:15 PM
Rage Maximus
4th Generation Maxima (1995-1999)
3
09-03-2015 12:26 PM
RealityCheck
4th Generation Maxima (1995-1999)
2
08-05-2015 06:18 AM



Quick Reply: Changed IACV, still driving with toasted ECM



All times are GMT -7. The time now is 04:37 PM.