Notices
Classic Trucks '47-'98 GM Trucks - Performance | Conversions | General Discussion

305 not running right

Thread Tools
 
Search this Thread
 
Old 12-07-2009, 05:09 PM
  #1  
Launching!
Thread Starter
iTrader: (3)
 
SSmikeSS's Avatar
 
Join Date: Mar 2006
Posts: 222
Received 0 Likes on 0 Posts
Default 305 not running right

I have a 1985 pick up with a 305. This just started this morning. The truck idles fine in park, as usual. As soon as I go into reverse or drive it idles real choppy and sputters. Cruising around at a steady speed and rpm it doesn't run too bad, but when I go up hill(at higher RPMs)it gets really bad(sputtering and no power).
I checked my plug wires and connections and checked for vacuum leaks. Everything seems to be OK.
What else should I check?
Thanks,
Mike
Old 12-07-2009, 10:02 PM
  #2  
TECH Fanatic
iTrader: (1)
 
Dewey's Avatar
 
Join Date: Dec 2008
Location: Huntsville, AL
Posts: 1,355
Likes: 0
Received 0 Likes on 0 Posts
Default

check the plugs, obviously. check the carb to see if it is flowing properly. check the dist. cap and rotor. is it misfiring? any frayed wires?
Old 12-07-2009, 10:44 PM
  #3  
TECH Fanatic
iTrader: (2)
 
03chevyroyce's Avatar
 
Join Date: Sep 2008
Location: Arlington TX
Posts: 1,238
Likes: 0
Received 0 Likes on 0 Posts
Default

egr??
Old 12-08-2009, 05:26 PM
  #4  
Launching!
Thread Starter
iTrader: (3)
 
SSmikeSS's Avatar
 
Join Date: Mar 2006
Posts: 222
Received 0 Likes on 0 Posts
Default

the plugs and wires are fairly new. What should I look for on the distributor? I'm pretty clueless when it comes to carbs also I took the EGR off a couple of years ago.

I changed the fuel filter today. That wasn't it. Could it be the fuel pump?

It only happens when I'm in gear. I revs really nice in park or neutral.
Any other ideas or info?
Thanks,
Mike
Old 12-08-2009, 06:04 PM
  #5  
The House is Rockin'
 
BLUES MAN's Avatar
 
Join Date: Mar 2008
Location: Under a moaning senorita
Posts: 2,576
Likes: 0
Received 0 Likes on 0 Posts
Default

distributor most likely as stated above...
Old 12-08-2009, 11:37 PM
  #6  
TECH Fanatic
iTrader: (1)
 
Dewey's Avatar
 
Join Date: Dec 2008
Location: Huntsville, AL
Posts: 1,355
Likes: 0
Received 0 Likes on 0 Posts
Default

change the distributor cap and the rotor button. shouldn't be too expensive and i'll betcha that is what is causing it.
Old 12-09-2009, 06:24 PM
  #7  
Launching!
Thread Starter
iTrader: (3)
 
SSmikeSS's Avatar
 
Join Date: Mar 2006
Posts: 222
Received 0 Likes on 0 Posts
Default

Well, it wasn't the cap and rotor.
I double checked the plug wires and vacuum lines, all looked ok. could I have a clogged Catalytic converter??? Still, Why would it only act up when I'm in gear?
Old 12-10-2009, 03:46 PM
  #8  
Launching!
Thread Starter
iTrader: (3)
 
SSmikeSS's Avatar
 
Join Date: Mar 2006
Posts: 222
Received 0 Likes on 0 Posts
Default

Anybody have any other ideas before I take it to a shop????
Old 12-10-2009, 03:51 PM
  #9  
Staging Lane
iTrader: (6)
 
Stangbanger's Avatar
 
Join Date: Mar 2003
Location: chestertown
Posts: 71
Likes: 0
Received 0 Likes on 0 Posts
Default

What kind of carb is on it?
Old 12-10-2009, 07:07 PM
  #10  
TECH Fanatic
 
ThrottleHappy7's Avatar
 
Join Date: Mar 2006
Location: L-ville, Texas
Posts: 1,055
Likes: 0
Received 0 Likes on 0 Posts
Default

I have an '86... 305 with a 4 barrel. I've experienced similar issues before... replaced plugs (which looked like charcoal) and the distributor cap and button (burned). To this day I have no idea how it was running, let alone firing. But if you've checked ignition, fuel filter and pump are good, and everything else looks good, I'd look at the carb. If it's not that... then I'd say you've got a good case of the gremlins.

The only other thing that I can think of is that there's a vacuum line that comes off the transmission on the passenger side, if it's not on there it might be the reason why you're revving fine in park and neutral, but not having much luck in gear.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
stealthperf
General Truck Racing and Discussion
34
02-14-2016 11:35 AM
The_W
FUEL SYSTEMS
4
08-15-2015 08:07 AM
Mossyoakglock
GMT 900 Trucks General Discussion
0
07-17-2015 08:30 AM
Mzay
GM Engine & Exhaust Performance
9
07-06-2015 11:03 PM



Quick Reply: 305 not running right



All times are GMT -5. The time now is 09:50 PM.