Belker

I've seen searching the archives and now I'm more confused than when I started.

My car ('91 RS 3.1 126k mi.) has been starting/running like crap for a few weeks and I just recently got it to give me a check engine light. It gave me a code 42 (EST problem).

The car was running perfectly fine and started on the first try. Then one day it wouldn't start until about the 10th try and would hardly idle without stalling. After it warmed up it idled fine but hesitated and stumbled from about 1000 to 2500 rpm. Above 2500 it runs pretty smooth but may have a little less power than it used to (kinda hard to tell).

I changed the fuel filter, checked the timing, and reset the computer by disconnecting the battery. This may have helped some and I can now usually start the car on the 1st or 2nd try. However, the car still runs like crap from about 1000 to 2500 rpm. It still hesitates and stumbles (I don't know how else to describe it). If I feather the gas in & out it will climb past 2500 rpm and seems to run ok at higher rpms.

Yesterday I attemped the 1st trip longer than 10 miles since I started having problems. I attemped a WOT accelleration and the car "had a heart attack" and the 'check engine' light came on. It barely ran enough for me pull off the road and it stalled. I tried restarting but it wouldn't. I popped the hood looked around for a couple minutes but found nothing. I tried starting it again, it started, and I drove home.

What do you think the problem is? What can I test or replace? What's wrong with my car? Any ideas?

BTW- the plugs, wires, cap/rotor, & coil were changed about 5000 miles ago. Everything else (except the fluids/filters, water pump, radiator cap, & serp. belt) is probably factory original. The car has 126000 miles.

Please help!

CaliCamaroRS

It's hard to tell without actually seeing the car.......but have you rebuilt the distributor recently? Or replaced the ignition module? Seems likely considering the car acts up under load.

Also check the WHITE wire and the TAN W/BLACK STRIPE wire coming out of the 4 pin connector at the ignition module. See if either of these wires are broken or damaged. Also check the EST connector (tan/ black wire) near the passenger strut tower.

If you want to rebuilt the distributor, here's what you need, along with GM part numbers:

-Ignition Module 10482827
-Pole Piece 1988010
-Pickup Coil 10495089
-Mainshaft 10497450
-Copper SHield 1989792

joezero

Like Cali said, check the EST wire (tan with black stripe). If it's become disconnected, shorted, etc. then you are only going to be running at your base timing, which is probably around 10*. This will cause your car to run really lousy, especially at lower RPMs. The first time I tried to set the timing in my camaro, I disconnected what I thought was the EST wire but wasn't. So you can imagine how shocked I was when I read 22* of advance with a timing light. What I didn't realize was that the base timing was set at 10* and the ECM was adding another 12* of advance. So I set it to 10* which put it at like 2* ATDC, so my car produced no power. It sounds like you have a similar situation. If you have access to a scan tool, use it to get your ECM advance (base timing + ECM advance) and then check it with a timing light. Hope this helps, Joe

KED85

Everyone beat me to it.
Also rebuild distributor and change the timing chain & water pump, too.
IF you really like the car, this is an ALL EFFORT PROJECT that will give great returns.

Belker

thanks. I'll take a look at the things mentioned.

CamaroStud1988

my friends truck did the exact thing,it got worse and worse then it died and wouldnt start after it did that a few times. his ignition module went out. thats my 2 cents.later

Belker

I changed my ingition module last night. I also checked out the wires mentioned and couldn't see any problems (although I'm gonna do it again in the daylight). The car still isn't running right at lower rpms.

(I'm gonna price the parts for a distributor rebuild.)

Any more ideas?

stuart69427

rebuilding the distributor does wonders, trust me, i had a really hard time starting my car, and it idled real rough, and the rebuild smoothed my idle and now it states in less than a second (if i let the fuel pump prime it first )

WTF ??? You do not need a "pole Peice" or "mainshaft" or "copper shield" so don't waste your money. I would send you to Karl's "Ked85" post on rebuilding the distributor, but i can't seem to find it ( which reminds me, Have you found it yet Karl? )

I used a "holley annhilitor Ignition module" which is the same price as the GM unit, but supposedly its better, and to me it is better than what i had before, but i don't know if mine was just bad or what...

Here is a qoute from Karl from a ealier post, but he has better instructions somewhere...

CaliCamaroRS

Whatever.....keep doing half-assed rebuilds. These parts are whats neccessary for a FULL rebuild.

stuart69427

As far as the mainshaft is concerned.. Why buy a new one ? ... some brake Cleaner cleans it all up, sand it down with some fine sand paper and re-lube it with synthetic grease...

And if were on the topic of a "Full" rebuild, why did you forget to mention the "gear" huh?

Belker

would installing a new pickup coil help my situation

I Cant Drive 55

If the pick-up coil is bad than it will help . Dont rule out a bad vacuum leak.
It does sound more like an ignition prblem though.

KED85

Dan, when I did do this distributor rebuild prior, that's what I followed.
I reused what parts I had in hand, the non wear parts.
I was able to "clean & restore" performance.
What are ya suggesting?

I really believe this "rebuild receipe" works great for many people here.

Only other detail I had to do to main shaft was slight filing to remove a little metal chip or two.

MOST DEFINETLY REPLACE THE CIRCLE SHAFT COIL!

IF still rough after this rebuild.
Vacuum leak or timing chain is shot.
To prove timing chain shot, loosen distb, twist toward firewall.
IF smooths big time out, you found problem.

Do you have over 50K miles & never replaced the chain? You need to do this, then.

AFrikinGoodTime

I just had the same problem two days ago, the car stumbled at low rpms. I first thought it was the control module (I keep a spare in the car at all times{DELCO}). This time that wasn't it, my advance was still jumping all over the place and the engine was bobbling hard. Pulled the distributor and rebuilt it and yes it was the pick-up coil.

CaliCamaroRS

You're right, replacing those parts is debatable.

There's 2 ways to look at it though. Here's my way: with a distributor, you don't know what needs to be replaced until you pull it out.....so I'd rather play it safe and replace everything, and not risk the possibly being stranded on the weekend because I can't find a part that I didn't buy, but now need.

Or the other way: pull it out and replace what you need to replace. This is no problem if you have multiple cars and you car can be in-op for a while.

Either way works.

joezero

I'm a little confused why you're "rebuilding" the distributor instead of just replacing it. I mean, it seems that you're replacing everything except the distributor shaft. Is it really that much of a price difference between parts for a rebuild vs. a whole new distributor? Or am I missing a bunch more pieces that aren't getting replace? Please forgive my being ignorant in this matter but I don't understand why you'd spend all day replacing every little piece when you could pick up a whole new one and be done in 10 minutes.

CaliCamaroRS

joezero,

As far as I know, you CAN'T buy a new distributor for our V6's. The aftermarket does provide new distributors for V8 cars, but I've never seen one for ours. And GM only sells the rebuild parts.

coolrimsatleast

I had what sounds like the same problem not too long ago. I replaced the coil with a blaster GM coil and also replaced the O2 sensor (seemed like maybe even the fuel mixture was messed up) at the same time. Didn't think to run car after replacing just one or the other so I don't know which actually caused problem. At 147,000 miles they were both probably original for all I know. Anyway that fixed it.

stuart69427

If you go to any auto partsd store and ask for a distributor, they will sell you a rebuilt one. I was qouted an average of $160 before the "core" charge for one. These places also sell the stuff you need to do the rebuild, like the pick-up-coil. Mine was falling apart, you couldn't tell it was a coil any more

Cali, I understand completly about being "safe" just that it isn't all that necessary...

KED85

I've discovered,
The higher the price for the parts, find the alternative or true cause of problem or alternative solution for fixing problem.
When it's called a non wear item, that tends to be a correct description.
The V-6 distributor is full of non-wear items, that just need a good cleaning and then add the few electronics to the non wear items (housing, shaft and contact pole).

TomP

I'll still suggest to use the one-inch inside diameter o-ring on the distributor shaft for the oil seal...

But I never replaced the things Dan mentioned, either. Granted, it's probably a good idea, especially after many miles. A cheaper alternative might be to score a distributor from a junkyard 2.8/3.1 with less miles on the motor. Then the shaft & related parts might be in better shape. My last distributor rebuild was in 1999, and it's been great so far. I want to rebuild it eventually with a Holley ignition module (summit # HLY-891-103) because it's a Borg Warner "stock replacement" module right now.

KED85

Tom,
As I am doing my 3.4 swap final details, I am going to use both items.
Rubber o ring (supplied)
and
The Small Block Chevy Distributor gasket
Also supplied in the Fel Pro rebuild gasket kit.
Why not....Cheap insurance

Visited Dan today.
He brought out a well worn V-8 distributor very similar to our V-6 design.
I was shown one shaft with LOTS OF WEAR and "Slippage" is kind way to phrase it.
I've known women that loose on top of a pole
When the distributor is apart and in your hand, you'll know what to replace or "rebuild".

CaliCamaroRS

It's true, most of the time you won't need to replace the mainshaft. But as Karl saw today, the magnet can come loose and cause poor running conditions, and the magnet can actually go bad.

The distributor I showed to Karl was 7 years old.....that's alot newer than ours, isn't it?

TomP

Karl, you know I have to bring that o-ring up every time you mention the gasket! Although I do agree the gasket would last longer than the o-ring.

Cali, the magnet can go bad? How? Because of the heat?

KED85

Tom, I know.
Part of the fun here
BUT......
When I removed my "magnets" they cracked in half.
Did I remove incorrect or was it heat damaged?
Sure....
Just one of those parts that tends to get more abused by servicing and removal I'll bet.
But, of the two 2.8 distributors I have (Blazer & Firebird) neither shaft was like the example shown me.
None of my V-8 distributors lying around, perform like that Lady Rotating on the top of the Shaft Pole, either.
But, as shown, parts wear out.
Even Non-wear items.

stuart69427

hmmmmm, i think i am going to check my magnet now

KED85

Yours is fine.
I was told why, when I presented my broken magnet & asked, "Do I need to replace this, it still is maganitized?"
Answer.
"Put it together, broken like in your hand, then tell me if you need to replace it. Make sure the truck starts so you can go get that part".

If not broken, its fine, as your vehicle does run.
I was careless when I removed mine.
Oh well.