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

Think these are classic low compression symptoms

Thread Tools
 
Search this Thread
 
Old 02-09-10, 07:25 PM
  #1  
Junior Member
Thread Starter
 
longpath's Avatar
 
Join Date: Feb 2010
Location: Stamford, CT
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
CT Think these are classic low compression symptoms

My car's Mazda rotary still seems to have plenty of power straight up to just before redline and starts fine when cold; but now she acts like the engine is flooded when trying to restart the engine when warmed up.

I'm pretty sure that if the problem was a plugged cat, I'd have no power once I got above idle. I'm also pretty sure the problem is not due to bad ignition. I'm running GMC Yukon coils and they were installed about 8000 miles ago. The Iridium plugs were swapped shortly afterward.

I also run 4-6 ounces of 2 stroke oil per tank of fuel as supplemental premix; but even that doesn't seem to help.

Am I right? Are these low compression indications? I'm trying to acquire a rotary-specific compression tester; but am having trouble reaching the vendor (Mazda's compression tester is way out of my budget). I'm also open to compensating someone who has a rotary compression tester for the use of their tester, and to travelling to them if they are anywhere between Hartford and Northern NJ.
Old 02-10-10, 10:38 AM
  #2  
Engine, Not Motor

iTrader: (1)
 
Aaron Cake's Avatar
 
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,791
Likes: 0
Received 113 Likes on 95 Posts
When was the last time the car had a tune up? Have the injectors ever been serviced?
Old 02-10-10, 11:22 AM
  #3  
Top Down, Boost Up

iTrader: (7)
 
RotaryRocket88's Avatar
 
Join Date: Mar 2008
Location: San Diego, CA
Posts: 8,718
Likes: 0
Received 6 Likes on 4 Posts
Hotstart issues are almost always due to 2 things: dirty injectors and/or the overly rich stock start map. Even with freshly serviced injectors, sometimes the start map is just too much to overcome. There are cheap band-aid fixes like fuel cut switches and tees for the fuel lines, but for bad cases the only true way to fix it 100% is with a programmable ECU.

If the car is an S5, the gas pedal can be held to the floor during cranking to shut off fuel. If the car is an S4, the 40A EGI COMP fuse can be pulled and replaced after clearing the flood.
Old 02-10-10, 11:24 AM
  #4  
Rotary Freak

iTrader: (7)
 
Go48's Avatar
 
Join Date: Feb 2005
Location: Mont Alto, PA
Posts: 1,608
Likes: 0
Received 3 Likes on 3 Posts
I have a customer in Coventry, CT who has one of our tester systems. He might be willing to test your compression. I will email him to ask him and have him contact you if he is willing. PM me your email address or phone number.

Larry
Old 02-12-10, 02:53 PM
  #5  
Junior Member
Thread Starter
 
longpath's Avatar
 
Join Date: Feb 2010
Location: Stamford, CT
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
CT

Originally Posted by Go48
I have a customer in Coventry, CT who has one of our tester systems. He might be willing to test your compression. I will email him to ask him and have him contact you if he is willing. PM me your email address or phone number.

Larry
Thank you, whether he's willing or not, I very much appreciate you asking.

The car is a 2004 RX-8 6-port with 48K miles. The last tune up was at 40K miles when new coils, plugs, and plug wires were installed.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
alexdimen
3rd Generation Specific (1993-2002)
20
10-23-15 01:50 PM
ZacMan
Build Threads
4
09-19-15 09:20 PM
Monsterbox
Adaptronic Engine Mgmt - AUS
5
09-11-15 03:29 PM
ZaqAtaq
New Member RX-7 Technical
2
09-05-15 08:57 PM



Quick Reply: Think these are classic low compression symptoms



All times are GMT -5. The time now is 09:15 PM.