Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

How to diagnose Bad Distributor

Thread Tools
 
Search this Thread
 
Old 12-30-2002, 11:10 AM
  #1  
Supreme Member

Thread Starter
 
tanager11's Avatar
 
Join Date: Dec 2001
Location: Brampton
Posts: 1,214
Likes: 0
Received 0 Likes on 0 Posts
Car: 91 Z28 Vert
Engine: 305
Transmission: TKO
Axle/Gears: 3.55 10-bolt
How to diagnose Bad Distributor

How do I go about checkign to see if my distributor is bad? OVer the last little bit the car would pull a no-start after short trips, and then re-start after sitting for a couple of hours, but yesterday it died again and I cannot get it re-started.

I seriously doubt it is fuel related since I cant even get it to run using quick start, and I also changed the Cap and coil with "good" ones and that did not change anything. I checked for a spark at the end of each of the sparkplug wires and yes there is a spark (sort of Orange in colour I might add). I am thinking that possibly the spark is not "hot" enough to get things going, and it might be a result of a bad distributor, but does anyone have any ideas or suggestions as to a) what it might be, or b) how to test for a bad distributor. Oh ya btw this is not on my Camaro but my winter beater, a 85 olds delta 88, 307, Carb.

Thanks,
Old 12-30-2002, 12:05 PM
  #2  
Supreme Member
 
RB83L69's Avatar
 
Join Date: Jul 1999
Location: Loveland, OH, US
Posts: 18,457
Likes: 0
Received 14 Likes on 14 Posts
Car: 4
Engine: 6
Transmission: 5
Try a rotor. If you haven't replaced it lately, you need one anyway, even if that's not your no-start.

If it still has trouble starting, it probably needs a module. Make sire when you replace it that you use the heat sink grease between the mosule and the dist housing.
Old 12-30-2002, 12:26 PM
  #3  
Member
 
felo72's Avatar
 
Join Date: Jun 2002
Location: Warren, OH
Posts: 242
Likes: 0
Received 0 Likes on 0 Posts
I agree, you can check the rotor just by looking at it to see how burnt up it is. As for the module, you can have them checked at any parts store. It sounds like the module is your problem.
Old 12-30-2002, 12:32 PM
  #4  
Supreme Member

Thread Starter
 
tanager11's Avatar
 
Join Date: Dec 2001
Location: Brampton
Posts: 1,214
Likes: 0
Received 0 Likes on 0 Posts
Car: 91 Z28 Vert
Engine: 305
Transmission: TKO
Axle/Gears: 3.55 10-bolt
I am going to look into that module, I am assuming, given the car etc, that it is something which is probably something which is relatively inexpensive, so probably worth while replacing even if it isnt gone.
Old 12-30-2002, 12:36 PM
  #5  
Member

 
Falconiroc's Avatar
 
Join Date: Nov 2001
Location: Midvale, UT
Posts: 482
Likes: 0
Received 2 Likes on 2 Posts
Car: 1991 RS
Engine: L03
Transmission: T5
Axle/Gears: 4.11
dont discount the fuel pump, Mine was the same way, it would die, then I wouldnt be able to start it again, until it cooled down, no matter what I did. Replaced the fuel pump and havnt had a problem since.

just a thought.
Old 12-30-2002, 03:54 PM
  #6  
Supreme Member

Thread Starter
 
tanager11's Avatar
 
Join Date: Dec 2001
Location: Brampton
Posts: 1,214
Likes: 0
Received 0 Likes on 0 Posts
Car: 91 Z28 Vert
Engine: 305
Transmission: TKO
Axle/Gears: 3.55 10-bolt
BTW....what does the Module do???? And if that was gone would it still crank over? I wouldnt think it would crank if that was the problem, but then again I dont really know what the module controls etc.
Old 12-30-2002, 04:55 PM
  #7  
Supreme Member
 
RB83L69's Avatar
 
Join Date: Jul 1999
Location: Loveland, OH, US
Posts: 18,457
Likes: 0
Received 14 Likes on 14 Posts
Car: 4
Engine: 6
Transmission: 5
The module is the thing that actually passes and then interrupts the curent through the coil, just like points used to do. It sees pulses from the pickup coil, and amplifies them to high enough power to make sparks.

Teh ignition module has nothing whatsoever to do with cranking. The car will crank just fine without it even installed; it just won't start.

Try a rotor first. That's the reason for about 90% of all ignition failures in that type of ignition system. I used to carry one around with me all the time, and got to meet a couple of pretty girls who were stranded by their cars that had stopped working, which I could revive in seconds with my spare. If that doesn't do it, change the module, which is inside the dist under the rotor. That's the reason for about 90% of the remaining failures.
Old 12-30-2002, 06:32 PM
  #8  
Supreme Member

Thread Starter
 
tanager11's Avatar
 
Join Date: Dec 2001
Location: Brampton
Posts: 1,214
Likes: 0
Received 0 Likes on 0 Posts
Car: 91 Z28 Vert
Engine: 305
Transmission: TKO
Axle/Gears: 3.55 10-bolt
awsome...thanks again.
Old 12-30-2002, 07:19 PM
  #9  
Moderator

 
AlkyIROC's Avatar
 
Join Date: Jul 1999
Location: 51°N 114°W, 3500'
Posts: 17,110
Likes: 0
Received 120 Likes on 101 Posts
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
I had to diagnose a hard start/run rough fault on a late 90's GM truck with a 454. After blowing the muffler off it from a backfire I traced the problem down to a bad distributor. It was one of those plastic body style. The top internal bushing was completely worn out. The shaft moved back and forth and caused intermittant spark. Since this style of distributor was not rebuildable I had to order a new one. Worked fine after that.

If it won't fire even on starting fluid then it's definitly an ignition problem. There could be other mechanical problems. Maybe the timing chain has stretched or jumped a tooth. The distributor drive gear at the bottom is held on with a roll pin/spring pin.

I've seen the pin break and the drive gear spins. Since you're getting spark we know it's still rotating. Pull the distributor cap off and pull #1 spark plug out. Bump the engine over until #1 is at TDC or very close to it (check the timing marks). Look to see where the rotor is pointing. If it's not pointing at the #1 plug wire then the drive gear is probably misaligned. The distributor will need to be pulled to be fixed.
Old 12-30-2002, 07:37 PM
  #10  
Supreme Member

Thread Starter
 
tanager11's Avatar
 
Join Date: Dec 2001
Location: Brampton
Posts: 1,214
Likes: 0
Received 0 Likes on 0 Posts
Car: 91 Z28 Vert
Engine: 305
Transmission: TKO
Axle/Gears: 3.55 10-bolt
Stephen....

Thanks for the suggestion on checking to see if the drive gear is spinning....I have put that down on my list of things to check, my only problem is that the car is waiting to be towed home by my buddy who said "oh sometime today or tomorrow I will be in your area to drop it off", so we will soon see, this problem has really ticked me off.

Thanks
Old 12-31-2002, 01:53 PM
  #11  
Supreme Member

 
TomP's Avatar
 
Join Date: Mar 2000
Location: Central NJ, USA
Posts: 13,414
Likes: 0
Received 6 Likes on 6 Posts
Car: 1986 Firebird
Engine: 2.8 V6
Transmission: 700R4
If when you get it home, it starts right up, I'd definately be thinking ignition module; common failure goes something like this: Car is cold, means module is cold, so car runs great. Car heats up, module heats up, module fails, you get stuck on the side of the road. Car cools down, module cools down, car runs great. Over & Over again! The fact that the car would restart after sitting for a few hours seems to say it's the module.

If you change it, go to Radio Shack and buy some of their heat-sink grease. It's a white grease, costs you about $3 for a tiny little tube, but it's the good stuff, and the key point is, you'll have extra grease. Sometimes you can run thin with those little packets they include with a new module.
Old 12-31-2002, 04:17 PM
  #12  
Supreme Member

Thread Starter
 
tanager11's Avatar
 
Join Date: Dec 2001
Location: Brampton
Posts: 1,214
Likes: 0
Received 0 Likes on 0 Posts
Car: 91 Z28 Vert
Engine: 305
Transmission: TKO
Axle/Gears: 3.55 10-bolt
Thanks....I have still yet to check on things with it...I got it towed back today and there is no way I am going to spend my new-years eve working on that thing! It still does not start, but the more I chat with people on here, the more it seems to point towards the module, I am going to give it a shot tomorrow, hopefully things work out with it....I will keep you guys posted.

dave
Old 01-02-2003, 09:33 PM
  #13  
Supreme Member

Thread Starter
 
tanager11's Avatar
 
Join Date: Dec 2001
Location: Brampton
Posts: 1,214
Likes: 0
Received 0 Likes on 0 Posts
Car: 91 Z28 Vert
Engine: 305
Transmission: TKO
Axle/Gears: 3.55 10-bolt
Go figure....I go out and give the Beast one last try at starting yesterday and it fires up after not starting for like 3 days and getting it towed home from Home Depot

Anyways, I pulled/replaced the plugs, wires, cap, rotor and module this evening. The plugs were NASTY, but I think I might have caught my problem. I think it might have been a combination of the nasty plugs and a Module on its way out, we will see how things are in the next coupel of days etc to see if the problem re-surfaces, if it does, I think I am going to take a hammer to that thing....Regardless thanks for your help guys
Old 05-15-2012, 03:29 PM
  #14  
Junior Member
 
Arciniega Jaime's Avatar
 
Join Date: Apr 2012
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Re: How to diagnose Bad Distributor

Did changing the module n plugs help your problem? I'm having the same symptoms with my camaro
Old 05-15-2012, 05:38 PM
  #15  
Supreme Member

Thread Starter
 
tanager11's Avatar
 
Join Date: Dec 2001
Location: Brampton
Posts: 1,214
Likes: 0
Received 0 Likes on 0 Posts
Car: 91 Z28 Vert
Engine: 305
Transmission: TKO
Axle/Gears: 3.55 10-bolt
Re: How to diagnose Bad Distributor

Wow is this one from the past! I vaguely remember this issue with my delta..what the end fix was I cant recall but think it may have been the module....man I miss that pimp machine!
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
86CamaroDan
Engine/Drivetrain/Suspension Parts for Sale
2
09-29-2015 10:08 PM
TheTraut88
TPI
6
09-11-2015 05:16 AM
mddaniel
Tech / General Engine
12
09-08-2015 05:16 PM
greenyone
TPI
3
09-02-2015 03:39 PM
RyanJB
TPI
0
09-02-2015 01:27 PM



Quick Reply: How to diagnose Bad Distributor



All times are GMT -5. The time now is 06:15 AM.