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

1981 Rx7 High School Shop Question Thread.

Thread Tools
 
Search this Thread
 
Old 04-08-13, 08:37 PM
  #1  
Junior Member
Thread Starter
 
culp7's Avatar
 
Join Date: Mar 2013
Location: Kansas
Posts: 24
Likes: 0
Received 0 Likes on 0 Posts
1981 Rx7 High School Shop Question Thread.

So I just got back from a tour of China and my car has recently been having some issues. Whenever I am driving it will just randomly die in traffic. Every time so far that it has died, I can usually give to between 10-20 minutes of sitting and it will start back up and run fine. It has been getting progressively worse and will die every 5 miles or so. So right now she is sitting until I diagnose the problem. My buddy in the shop I had bought the car from says he replaced a lot of the electrical components in the ignition. So I'm thinking it might be the fuel pump going out. However, right after dying I can turn the key on and still hear the pump running. Could it be running, but on its last leg and not pumping well? Also pumping the gas several times sometimes might decrease the amount of time it sits before it will start again. Does anyone have any suggestions on something else it might be? Or am I on the right track here...?
Old 04-08-13, 10:52 PM
  #2  
Junior Member
Thread Starter
 
culp7's Avatar
 
Join Date: Mar 2013
Location: Kansas
Posts: 24
Likes: 0
Received 0 Likes on 0 Posts
Also, Its a 12a
Old 04-08-13, 11:16 PM
  #3  
Moderator

iTrader: (3)
 
diabolical1's Avatar
 
Join Date: Feb 2002
Location: FL
Posts: 10,811
Received 305 Likes on 266 Posts
welcome.

start with a fuel filter. cheap. and probably needs changing anyway. no loss even if that's not the issue.
Old 04-08-13, 11:24 PM
  #4  
Junior Member
Thread Starter
 
culp7's Avatar
 
Join Date: Mar 2013
Location: Kansas
Posts: 24
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by diabolical1
welcome.

start with a fuel filter. cheap. and probably needs changing anyway. no loss even if that's not the issue.
That was something I had also thought of. But according to the previous owner, it had been done about 2000 miles ago. Might go head and throw a new one on there anyways... However the car was $900, rebuilt 15k ago, and has about 128k miles total on her. I'm just ready to find out whats wrong and get back on the road before I go to bootcamp!
Old 04-08-13, 11:30 PM
  #5  
Moderator

iTrader: (3)
 
diabolical1's Avatar
 
Join Date: Feb 2002
Location: FL
Posts: 10,811
Received 305 Likes on 266 Posts
pish posh on what the previous owner said. 2000 miles ago doesn't matter. these cars can be pretty finicky with those filters. it really comes down to how much crap is swirling around in the tank.

it's new to you and you should just do a full tuneup. the pump may actually be at fault, but i think it might be the wiser move to tune it up and see what happens.
Old 04-08-13, 11:42 PM
  #6  
Junior Member
Thread Starter
 
culp7's Avatar
 
Join Date: Mar 2013
Location: Kansas
Posts: 24
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by diabolical1
pish posh on what the previous owner said. 2000 miles ago doesn't matter. these cars can be pretty finicky with those filters. it really comes down to how much crap is swirling around in the tank.

it's new to you and you should just do a full tuneup. the pump may actually be at fault, but i think it might be the wiser move to tune it up and see what happens.
As far as a tune up goes, so far I have only done spark plugs. The spark plug wires look new and I think I'll go pick up a new fuel filter tomorrow. What else would you recommend for a full tune up? I'm new to rotaries and cars in general.
Old 04-09-13, 09:41 AM
  #7  
Moderator

iTrader: (3)
 
diabolical1's Avatar
 
Join Date: Feb 2002
Location: FL
Posts: 10,811
Received 305 Likes on 266 Posts
just basics ... plugs, cap, rotor, wires (but it's your call since you said they might have been recently replaced), filters (fuel, oil, air), oil and any other fluids that you don't know the history of or are on schedule. it's not a good practice to trust a previous owner. even if they're not trying to actually deceive you, they simply might not know certain things and maintenance, though it may not always be fun, it's always better than repair.

i do those things and more for any car that's new to me.
Old 04-09-13, 09:01 PM
  #8  
Junior Member
Thread Starter
 
culp7's Avatar
 
Join Date: Mar 2013
Location: Kansas
Posts: 24
Likes: 0
Received 0 Likes on 0 Posts
There also is another thing I was worried about.. When I am driving the car and get over about 20mph a weird "wopping" like sound comes form the rear end. As the car speeds up so does the sound. And sometimes after I drive for a little bit it will just stop and sometimes come back.. Anyone have any ideas on what this could be??

Also, for the problem described above it tends to die more often the harder I push the car...

But yeah I'll have to go pick up some parts and see if things change... Thanks for the advice Diabolical
Old 04-09-13, 11:10 PM
  #9  
Junior Member
Thread Starter
 
culp7's Avatar
 
Join Date: Mar 2013
Location: Kansas
Posts: 24
Likes: 0
Received 0 Likes on 0 Posts
Also with having the 4x110 wheels, I am having trouble finding good aftermarket ones for the car. I heard somewhere that fox body mustang rims will fit, is this true? Also wondering the same with the 4x114.3 rims...
Old 04-10-13, 11:07 AM
  #10  
Junior Member
 
EZEdChicago's Avatar
 
Join Date: Apr 2013
Location: Chicago, US
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Diabolical--Your suggestion on fuel filter is timely for me too. My tech was arguing that it was unlikely to cause the inconsistent idling in my 83 S, but there's visible debris in the bowl so I'm going to swap it out anyhow. Thanks.
Old 04-10-13, 01:30 PM
  #11  
Moderator

iTrader: (3)
 
diabolical1's Avatar
 
Join Date: Feb 2002
Location: FL
Posts: 10,811
Received 305 Likes on 266 Posts
well, if your only problem is the idle, then your tech is probably right. by the time the filter alone would significantly affect idle, the car should be showing serious issues while driving (sudden sputtering, hesitating, stalling, etc.).

as i said, filters are cheap and you lose nothing by changing them, so go ahead. it can't hurt, but are there other issues besides your idle?
Old 04-13-13, 09:08 PM
  #12  
Registered User
 
RRR Motorsports's Avatar
 
Join Date: Apr 2013
Location: santa ana
Posts: 60
Likes: 0
Received 0 Likes on 0 Posts
also u might need to take ur carb apart a check the jets inside
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
ItsJBohmzB
Build Threads
171
04-24-17 01:11 PM



Quick Reply: 1981 Rx7 High School Shop Question Thread.



All times are GMT -5. The time now is 06:20 AM.