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

93 FD Rx-7 rough idle on cold start (with video)

Thread Tools
 
Search this Thread
 
Old 05-05-12, 10:21 AM
  #1  
Full Member

Thread Starter
iTrader: (2)
 
OsterFD3S's Avatar
 
Join Date: Aug 2011
Location: Ontario, Canada
Posts: 85
Likes: 0
Received 0 Likes on 0 Posts
ON 93 FD Rx-7 rough idle on cold start (with video)

Hey guys hoping to get this problem diagnosed and i thought the best way to do this was to make a video of exactly the problem instead of trying to write it out, but i will give you guys a quick crash course as to the problem anyways. When starting my car from a cold start my idle will jump right around the 2 grand mark for a good 3-4 minutes but will slowly go away into a strong steady idle (as seen in video). I'm hoping my very knowledgeable rx7 community can help me find and solve the problem or just tell me it's nothing major and to leave it.

It's worth noting my car is completely stock at this time however i just recently purchased and new intake (pettit) and AST as well as some maintenance things (fuel filter all that jazz). I thank you guys for your time and i apologize for the mediocre quality of the video and my lack of the English language at the end of the video hahaha what i was trying to say was "leave a comment in the comment box"

Video link: http://www.youtube.com/watch?v=giuoY...ature=youtu.be

Thanks again guys
Old 05-05-12, 02:31 PM
  #2  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,011
Received 862 Likes on 611 Posts
The loping idle makes me think of a vacuum leak. I'd expect it to improve as it warms up, but not sure why it goes away.
You might try cleaning the Idle Air Control Valve (IACV..or sometimes just referred to as the IAC). They don't often go bad, but apparently get dirty from the PVC emptying into the manifold nearby. SEE FSM
I cleaned mine once..just because. Used a little brake parts cleaner and got a surprising amount of black soot/gunk out. It's on the aft side of the upper intake manifold...iirc two 10 mm nuts and a single connector. Again, not sure that will solve it, but it won't cost much to try. Maybe someone else will chime in with a better idea.
Old 05-05-12, 03:20 PM
  #3  
Zoom Zoom

iTrader: (7)
 
Jeff5808's Avatar
 
Join Date: May 2008
Location: Bay Minette, AL
Posts: 215
Received 0 Likes on 0 Posts
Very nice FD. Could be a vacuum leak, or IAC like Sgtblue suggest, or a bad solenoid. Does it still have the stock vacuum hoses? If so you should go with a silicone hoses, look a www.hosetechniques.com for a kit. Or you could go with viton hoses, a little more expensive but it will last a goon's age. Not sure where you could get it though.

Because cleaning the IAC would be easier, I would try that first.

Is the boost pattern normal? 10-8-10?
Old 05-05-12, 04:09 PM
  #4  
Can Post Only in New Member Section
 
jcrash586's Avatar
 
Join Date: May 2010
Location: new jersey
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
I'm having the same problem. Let me know how you make out.
Old 05-05-12, 05:25 PM
  #5  
Junior Member
 
shiznizzletech's Avatar
 
Join Date: May 2012
Location: Sarasota, FL
Posts: 36
Likes: 0
Received 1 Like on 1 Post
My 88 was doing that until today. I changed the throttle position sensor (TPS) and it runs great. I believe you are having the same issue since mine ran for about 5 minutes the same way until it warmed up. When warm it idled fine. Guarantee this will do it for you. Good luck and please let me know how the project goes. Cheers!

Last edited by shiznizzletech; 05-05-12 at 05:29 PM.
Old 05-05-12, 05:27 PM
  #6  
Junior Member
 
shiznizzletech's Avatar
 
Join Date: May 2012
Location: Sarasota, FL
Posts: 36
Likes: 0
Received 1 Like on 1 Post
Also, look on ebay for the sensor. It saved me about $175 on the price.
Old 05-05-12, 09:44 PM
  #7  
Full Member

Thread Starter
iTrader: (2)
 
OsterFD3S's Avatar
 
Join Date: Aug 2011
Location: Ontario, Canada
Posts: 85
Likes: 0
Received 0 Likes on 0 Posts
Thanks for all your guys inputs i'm literally going to try everything suggested so far.

Jeff- yes it still has the stock hoses i plan on changing those very soon so thank you for the link and also my boost pattern is normal running a 10-8-10
Old 05-05-12, 10:45 PM
  #8  
Zoom Zoom

iTrader: (7)
 
Jeff5808's Avatar
 
Join Date: May 2008
Location: Bay Minette, AL
Posts: 215
Received 0 Likes on 0 Posts
You can check the TPS with a volt meter, here are some links on what to do.
http://www.fd3s.net/tps_adjustment.html
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/fixed-my-idle-problems-backfiring-bucking-more-170731/

Good luck!
Old 09-12-18, 04:31 PM
  #9  
Junior Member
 
ValkyrieJax's Avatar
 
Join Date: Jul 2017
Location: Jacksonville
Posts: 24
Likes: 0
Received 1 Like on 1 Post
Oster-
Did the TPS solve your problem? Having the same issue.
Old 09-13-18, 03:41 AM
  #10  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,011
Received 862 Likes on 611 Posts
OsterFD3S hasn't been on the forum in about a year.
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
sherff
Adaptronic Engine Mgmt - AUS
9
02-24-19 12:09 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: 93 FD Rx-7 rough idle on cold start (with video)



All times are GMT -5. The time now is 09:00 PM.