Hey guys, I have a few questions about the distributor on my 89 GMC Suburban V1500

TBI 350

Is the pickup coil supposed to spin while the engine is off? I can physically spin the pickup coil back and forth about a 1/4 turn. The windings look rusty or reddish, and it doesn't seem to be spinning freely (if it is supposed to spin at all).

I also have red dust, not alot, but its there, inside the cap. Time to replace the distributor??

I am still troubleshooting my hesitation, backfiring, lack of power issue.
Thanks!
Ryan

 

Test each terminal of the pick up coil and ensure there is no continuity to ground. Then OHM out both terminals. Should be between 500-1500 OHMs. If any of these are out of spec, then the pickup coil is NFG. I think the pickup coil does move a bit, been a while since I checked.

 

Sailor6, Yikes that can't be good, 1/4 turn? Are you sure it's not just the outer shell moving? Sounds broken anyway, those are not a physical/mechanical advance diz, and the pickup is screwed down.
Your best bet is to head to the parts house & eyeball one of their remans.
I've seen those pickup shells wiggle back & forth slightly, but not even without some force or as far as say a vac advance plate moves.
I'd replace the whole diz. cuz you gotta pull it anyway to change the pickup.

 

I am sure its not just the shell, because I saw the whole thing move around the dizzy shaft. It is at least a quarter turn if not a little more, and it feels like something is broken.

i will get the dizzy replaced, but it may not be until next weekend. My "car maintenance" budget has been exceeded by quite a bit!

 

You have money to budget?? lucky dog..

Some dizzys have no shell, it's all exposed.
If you have any choice be sure to get the GM module w/ last 3#'s 369, very important.

 

still haven't picked up a new distributor...but a few more symptoms have shown up. Now, when I start it, it will start after a few cranks like it always does, rev up like usual, then die. No warning, nothing, just dies. It will start right back up, and do it again. If I put my into it, it will stay running, then idle rough like its been doing.

Another thing I've noticed is I can hear a grinding in the engine compartment, sounds like its coming from the distributor.

Another thing, but not sure if it is related, the starter is hanging up after starting, and I can hear it whirring away after its started for a few seconds, like it doesn't immediately let go after it starts the car.

 

Are the bolts tight? If loose the gear can hang up.
Or
The solenoid may be sticking.

 

It just started in the last 2 days, but I am going to check the bolts...could this distributor issue cause issues with the starter??

Other notes: I've tried several different timing settings, had it at 6*, then brought it down to 4*, tried it at 0* then up to 8* doesn't seem to make the slightest difference on how it runs. The missing is getting worse and worse, and now even giving it a little bit more than regular throttle, it bogs down really bad and backfires. Very Very strong gas smell from the tailpipe, and the inside of my pipe is soot-black. (brand new exhaust). I wonder if all this soot is causing my 02 sensor to give false readings making the truck run worse and worse...im sure it isn't helping!

Anyways, that is all for now....

 

First the o2, ya fouled they become unresponsive & may have a hard time getting to closed loop. Just soot normally burns/blows off with no lasting effect, other contaminants (oil, antifreeze ect.) or very heavy buildup are a different story & can ruin it.
She has probably fouled some plugs by now & will continue to get worse, as problems are compounding now.

I don't think you will get anywhere adjusting the timing till the pickup is squared away & plugs are changed.

The starter is also suffering from abnormally heavy use, given repeated restarts. Sticky solenoid, broken return spring, worn or broken actuation arm, worn or broken bendix or just a plain worn motor may await discovery.

The two problems are unrelated other than the starter has been getting a heavy workout.

 

I can understand why the starter is acting up...multiple restarts etc...

I am replacing the distributor this weekend...along with the EGR. I will pull the plugs and take a look, and replace if necessary (i am sure it is necessary). That sucks because I just put these ones in.

After that, I will pull the 02 to see how gummed up it is, and if it is going to have to be replaced again or not. I bet I don't even have 50 miles since replacing the plugs and o2 sensor!

Thanks!
Ryan

 

Ryan, leave the o2 be!
After you get clean plugs in & you run it some have a look @ o2 data.

Nobody gonna hate you for cleaning a little soot off your plugs w/ spray carb clean & compressed air, don't wire brush or bead blast them, trust me, they are new, just use chemical & compressed air.

I musta missed the EGR discussion.. always good to have a known solid factor.

 

I will definitely try that before buying new ones, Ive already thrown too much money into this thing...Thanks for the tip! I will let the o2 be for now. I will report back when I get the distributor in...ill wait on buying a new EGR for now and see what the distributor and cleaned plugs do first. thanks for the tips!!
Ryan K

 

New distributor + new plugs (cleaned) = no change....I did notice soot on #4 plug, and some whitish brown deposits but not much on #1. All the rest looked good.

still sputters right off takeoff (1500rpm or so, not on takeoff, still have black smoke, and the idle is really low in gear, and comes up in park or neutral. Seems to idle a lot better, no misfires at idle now that I can tell. No ticks, clacks, or knocks,.....checked operation of EGR (haven't pulled it yet to check it out). When I reach down and depress the EGR plunger, the engine responds to it.

Going to the shop on Monday, I needed the truck this weekend, and it is still not usable. I'm at my wits end!!

I may pull the coil and get it tested...its new...but when I rev it up in neutral, no missing, popping or anything, it is nice and smooth. When under load, it misses.

 

Well understand that your computer is trying to adjust from it's last known quandary..

Disconnect batt. to reset computer.

Reset, and let me make this clear, the diz to 0, not the running timing, the diz to #1 plug terminal, when #1 cyl is tdc compression stroke.

If you don't know exactly how to, take to a mechanic that does.