New Member RX-7 Technical Post your first technical questions here, in an easy flame free environment, before jumping into the main technical sections.

Bad Idle during Cold Start

Thread Tools
 
Search this Thread
 
Old 09-21-08, 04:33 PM
  #1  
whatever you liiiiikkkeee
Thread Starter
iTrader: (4)
 
sakura_FC's Avatar
 
Join Date: Sep 2008
Location: Irvine, CA
Posts: 389
Likes: 0
Received 0 Likes on 0 Posts
Unhappy Bad Idle during Cold Start

Let's start from the beginning:

My idle was really bad and I threw a CEL. I checked what the CEL was reading and it gave me code 12 (wide TPS). I picked up a good TPS from the forum and installed it. I cleared the CEL and warmed up the car. I threw another CEL and it gave me code 18 (narrow TPS). I used the two LED test method to adjust my TPS. My idle during normal operation is right on and smooth, but my cold start idle is really rough. It bounces from about 800rpm to 1500rpm. Also, when I turn the ignition to the "ON" position, my SAFC reads 43.3% Air Flow. My thermowax seems to be operating properly, but I'm not sure. Does this mean I have a bad AFM? Will this cause my cold start idle to bounce? My vacuum gauge reads a steady 500 mm/Hg during normal operating temps, so I know I don't have a vacuum leak.
Old 09-22-08, 12:29 AM
  #2  
whatever you liiiiikkkeee
Thread Starter
iTrader: (4)
 
sakura_FC's Avatar
 
Join Date: Sep 2008
Location: Irvine, CA
Posts: 389
Likes: 0
Received 0 Likes on 0 Posts
BTW the car is a 1990 NA. I've done the search and it has helped me up until this point.
Old 09-22-08, 01:30 AM
  #3  
whatever you liiiiikkkeee
Thread Starter
iTrader: (4)
 
sakura_FC's Avatar
 
Join Date: Sep 2008
Location: Irvine, CA
Posts: 389
Likes: 0
Received 0 Likes on 0 Posts
Well, after a full day of searching, I finally found a good link to the FSM. Then I remembered that I saved a copy of the FSM on my laptop a few years back. At any rate, I'm going to do a resistance test on my AFM tomorrow and I'll post up the results.
Old 09-22-08, 05:53 AM
  #4  
Bay Area Rotary

 
wakazz's Avatar
 
Join Date: May 2008
Location: Concord CA
Posts: 24
Likes: 0
Received 0 Likes on 0 Posts
hmm

Ok i had really bad idle on my cold start too. My friend had me disable the cold start and then adjust the default idle setting.
Old 09-23-08, 02:01 AM
  #5  
whatever you liiiiikkkeee
Thread Starter
iTrader: (4)
 
sakura_FC's Avatar
 
Join Date: Sep 2008
Location: Irvine, CA
Posts: 389
Likes: 0
Received 0 Likes on 0 Posts
I just finished with the resistance check on the AFM. It turns out that it's bad. I'm going to hunt for one and update after the install.
Old 09-24-08, 03:09 AM
  #6  
Junior Member

 
joshrulz's Avatar
 
Join Date: May 2007
Location: brisbane
Posts: 42
Likes: 0
Received 0 Likes on 0 Posts
cold heatrange plugs would not help cold starts as ive found with my b9 and b10egv's
Old 09-24-08, 10:27 AM
  #7  
whatever you liiiiikkkeee
Thread Starter
iTrader: (4)
 
sakura_FC's Avatar
 
Join Date: Sep 2008
Location: Irvine, CA
Posts: 389
Likes: 0
Received 0 Likes on 0 Posts
I'm using standard NGK rotory engine spark plugs (I'm assuming that you mean cold spark plugs). I'm still waiting on the AFM, but I doubt that is what is causing my cold start idle to bounce. Do you think the ECU is doing intentionally bouncing the idle because the TPS is a new unit?
Old 10-04-08, 05:14 PM
  #8  
Full Member

 
Obie2kenobe's Avatar
 
Join Date: Oct 2008
Location: Denver
Posts: 61
Likes: 0
Received 0 Likes on 0 Posts
I have a 94 that I just bought that is doing this same thing the engine was rebuilt less than 5k miles ago. Runs great other than that. It also seems to run pretty hot...the temperature gauge is fine but it just smells hot. Is that normal for these cars or something I should look into?

Obie
Old 10-05-08, 07:47 AM
  #9  
whatever you liiiiikkkeee
Thread Starter
iTrader: (4)
 
sakura_FC's Avatar
 
Join Date: Sep 2008
Location: Irvine, CA
Posts: 389
Likes: 0
Received 0 Likes on 0 Posts
Got a new working AFM. It helped out a little bit, but I still get the jumpy idle at cold starts.
Old 10-05-08, 12:33 PM
  #10  
Mez
Deus Ex Machina

 
Mez's Avatar
 
Join Date: Sep 2008
Location: BC
Posts: 58
Likes: 0
Received 1 Like on 1 Post
Originally Posted by Obie2kenobe
I have a 94 that I just bought that is doing this same thing the engine was rebuilt less than 5k miles ago. Runs great other than that. It also seems to run pretty hot...the temperature gauge is fine but it just smells hot. Is that normal for these cars or something I should look into?

Obie
From what hear (and also smell when i open the hood of my car ) these cars do run pretty hot so your good to go
Old 10-09-08, 05:42 PM
  #11  
Full Member

 
Obie2kenobe's Avatar
 
Join Date: Oct 2008
Location: Denver
Posts: 61
Likes: 0
Received 0 Likes on 0 Posts
Sorry to kinda jack your thread. So I have been still having those troubles. It seems to happen alot less if I don't put it in a gear at stop. If I put it in any gear then it seems to want to do the jumpy Idleness. Are you having the same issue, cuz mine happeness at hot and cold but only like 1 out of every 12 lights.
Old 10-10-08, 06:49 AM
  #12  
Junior Member
 
STIGMAdrift's Avatar
 
Join Date: Oct 2008
Location: COB Speicher, Iraq
Posts: 16
Likes: 0
Received 0 Likes on 0 Posts
Crazy, my little brother's does the same thing... Of course, his also smokes like a son of a bitch until the car warms up, then runs like a champ, lol
Old 10-11-08, 03:11 AM
  #13  
whatever you liiiiikkkeee
Thread Starter
iTrader: (4)
 
sakura_FC's Avatar
 
Join Date: Sep 2008
Location: Irvine, CA
Posts: 389
Likes: 0
Received 0 Likes on 0 Posts
It only happens during cold start. Once the temp goes up, I'm good.
Old 10-11-08, 04:10 PM
  #14  
Full Member

 
Obie2kenobe's Avatar
 
Join Date: Oct 2008
Location: Denver
Posts: 61
Likes: 0
Received 0 Likes on 0 Posts
Ok then definetly a different problem. If you search it, the forums have about a billion different things to try so if you have the time then I would start looking into those but if you just want to pay someone to fix it then that would probably be the easiest.
Old 10-12-08, 11:44 AM
  #15  
whatever you liiiiikkkeee
Thread Starter
iTrader: (4)
 
sakura_FC's Avatar
 
Join Date: Sep 2008
Location: Irvine, CA
Posts: 389
Likes: 0
Received 0 Likes on 0 Posts
I honestly might end up paying someone, or dealing with it until I do a turbo swap. I've looked up all that info and tried most of that stuff, and nothing has worked.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
trickster
2nd Generation Specific (1986-1992)
25
07-01-23 04:40 PM
Kyo
2nd Generation Specific (1986-1992)
6
04-13-19 09:24 AM
stickmantijuana
Microtech
30
04-23-16 06:37 PM
alphawolff
1st Generation Specific (1979-1985)
17
11-17-15 05:57 PM
ncds_fc
New Member RX-7 Technical
1
08-15-15 10:06 AM



Quick Reply: Bad Idle during Cold Start



All times are GMT -5. The time now is 09:46 AM.