GSL-SE_84

I wrote a whole history here, hoping it would help anyone else with my same

problems, and also help you guys help me find the problem.

I finally got a some good time to work on the car this weekend.

This is an '84 GSL-SE. I've had trouble with surging/lurching since I bought it in

January. It's worst at 2500 rpms on a flat road holding the throttle steady.

Here is what I did before this weekend...

Went through all of the "Solving GSL-SE idle problems" info and adjustments, and did

not get resolve.

Tested the resistance on the TPS and got bad numbers... Replaced the TPS and

adjusted. A little better, but still there.

Someone suggested unplugging the O2 sensor, and when unplugged, it got better. So I

replaced the O2 sensor. After that, the surging got worse...I'd describe it more as

bucking almost. And the backfires got worse. Also, when I first would start it

cold, it would run up to 2500 rpms, then drop and almost stall, then come up to 800.

Then this weekend...

Replaced plugs. The old ones looked beat. This made the bucking better, and now we

it was back to surging.

Recleaned the throttle body. It was dirty. Then it started idling at 1900 rpms.

Strange.

I adjusted the idle with the air adjustment screw, and the lowest it would go is

1500.

I cleaned the BAC, and ASV, and installed new gaskets because the old ones were

beat.

Idle was still at 1500.

At idle, I pressed the throttle linkage down, and it moved significantly, dropping

the rpms. I looked around for what was hanging it up, and figured out it was the

cruise control. I cut that out with wire cutters. It was all frayed up at the end

where the canister thing is. Who wants cruise anyway, that's no fun. That dropped

the rpms, and then I readjusted the TPS and idle and got it to 800 again.

The next day, I started it up, and the idle went to 700. I kicked it up to 2000,

and it landed on 1700, and hung there. Over the next 5-7 minutes it was dropping

slowly as the car warmed up. It's done this for months. Is this supposed to

happen?

Once it warmed up, I reajusted the TPS and idle and got 800.

While standing still and taking it up to 2000-2500, it sounds like it is missing...
Hum... could this be a spark problem not a fuel problem?

I look at the wires, removed them, and put them back on snugly. The wires are

definately not new... Not too old, but I'm going to replace them. I think to myself

"I wonder how old the cap and rotor are?"... and "what else causes missing in

these?" (After posting this I'm going to search on "missing").

I stop by pep boys, but they only have Borg and Warner 7mm wires, and I have NGK 8mm

now. I think I want 8mm since I read it somewhere, but I'm not sure. I pass on the

pep boys wires. What wires would you buy? I also think to myself "I should just

replace the whole ignition since I want to do that anyway, I wonder if I should do

that now...a hotter ignition with hotter wires?" What would you guys do?


The current status of the car...

It drives much better than before this weekend. It still surges/lurches at

2000-3000 rpms on flat ground at steady throttle (and other times but not as much).
It backfires(small ones) at the top of gears, or after being on it and letting off

suddenly. It sounds like it is missing if in neutral and at around 2000 rpms. I

believe the TPS, BAC, ASV, throttles, and other things in "Solving GSL-SE idle

problems" are all working properly and adjusted correctly.

What should I try now? Do fuel problems cause it to sound like it's missing, or

should I pursue the wires, cap and rotor avenue or something else.

Thanks,

Brad
84 GSL-SE

rxseven

Your problem seems to be sticking throttle plates. Clean the entire throttle assembly and lube it up. A slight problem here causes big changes in idle and causes surging. As an example, I had diassembled the assembly to clean it once and when i put it back together, it would idle high and then surge. Turned out I had over-tightened the end retaining nuts. Loosened them slightly and everything was back to normal.

GSL-SE_84

Would sticking throttle plates cause it to sound like it is missing?

I have the shop manual, and it says remove the:

Air funnel, Accelerator cable, Throttle sensor connector, metering oil pump connecting rod, and water hoses. No problem.

How does the Throttle chamber itself come off? It looks like two top bolts, are there bottom bolts?

I've already cleaned it with carb cleaner and wd-40 without taking it off. After taking it off, how is the best way to clean it? Do you just spray carb cleaner?

Max7

I'm on my 2nd GSL-SE with the same problems, tried many cures, so with good results, others bad.
I've just learned to live with it, install the engine tq brace seemed to smooth out the surging, since the engine will not rock around while bucking.
I will eventualy solve the problem with a Haltec and a T2 motor

sunray

Ever since I bought my car last year. There has been idling/surging problems. I can you tell how I licked about 90% of it. First off I'm a non-mechanic so please excuse the layman terms.
The first thing I do is to spray the entire surface assemblage of springs and levers with wd40 once a week. I know it makes a difference because when I have neglected it the surging comes back.

Second, there was a long spring that I changed that controls throttle speed. the temper had changed due to it being in a fire, courtesy of the last owner. this allowed me to drop the idle.

Third, I used one of those fuel injector treatment thingyies to clean the injectors and hoses etc...

I have no problems in the city and and highway speeds where the tach is above the magic "2500" is avoided. Before if I drove around 60km/hr at an rpm of 2000-2500 for more than 15 minutes I would run into the surge issue but it doesn't happen that often now. When it does I drop the gear and leave it up for a minute and that seems to do the trick.

I hope this helps

GSL-SE_84

Where is this long spring?

Do you mean injector cleaner that you put in the gas tank?

gump

I think that long spring is the one that extends when you open the throttle. It returns the throttle to it's stopped position. I feel your pain. I had a heck of a time getting my SE to run right, with similar problems to you. Finally, I found my throttle plates were not closing all the way, all the time, when I let off the gas. As of right now I've taken the whole throttle body off and cleaned all the carbon build up out, and I cut that long spring down a little bit, which provides a bit more strength in returning the throttle plates to their normal idling position.

GSL-SE_84

How does the Throttle chamber itself come off? It looks like two top bolts, are there bottom bolts?

I've already cleaned it with carb cleaner and wd-40 without taking it off. After taking it off, how is the best way to clean it? Do you just spray carb cleaner?

gump

There are two top bolts and two bottom bolts. Both 12mm. You need to first unbolt the two bolts that hold the large air tube that runs to the air filter to the throttle body. You also have to unconnect the linkage to the oil metering pump (metal rod that goes down the front of the engine), and the throttle and cruise control linkage (easy). There are two hoses that carry antifreeze that connect to it as well. Might want to plug these up after dissconnecting them.

I tried cleaning mine with carb cleaner too first without taking it off, and you really can't get to the plates in the back of the unit while it's bolted on. Once I had mine off, I used carb cleaner, paper towels, and q-tips. Spray, then wipe. Here's a pic of what the back of mine looked like after I took it off, before I cleaned it. The bottom plates and shaft were very gummed up. The top plate was allready partialally cleaned from me trying to clean it without taking it off.
Picture of dirty throttle plates

GSL-SE_84

Thanks for the great description. I won't have any problem now.

I can't get to your picture...

Keaponlaffen

to get the picture, open a new window, and paste in the link's source.... it's geocities' way of preventing you from linking to stuff on your site, to prevent you from using your space as a storage facility...


Jeff

rxseven

I would NOT mess with removing the upper intake if i were you. Focus on the throttle assembly first. Removing the upper intake will result in you having to spend a lot of time scraping the old gasket, then getting a new one. Further with this particular set-up, chances are you may have a vaccum leak when you put it back further complicating your surging problem.

GSL-SE_84

I got the pic. Thanks. That was really dirty. My car is really clean compared to many of the pictures I see. I'm not saying that mine aren't, but even the linkage and the outside parts... My car must have been in a garage all it's life or something. I'll try removing it and cleaning well this week.

About the other post...
I'm going to remove the throttle assembly only, not the intake. I don't think I'd venture that far. It would go to KD Rotary for that.

Thanks.

GSL-SE_84

Today I replaced the cap, rotor and wires. All of these were beat. The greatest sight was the cap which had a large crack and was definately contributing to the problem. Overall the cap and rotor were well worn and the wires were old. Here's a picture of the cap http://www.waytoogood.com/cap.htm

The car now has so much more power, and much less hesitation. It has a whole new sound. Crisp and crackly exhaust note. Much faster. However, I still have a surging on flat ground at constant speed. I have many other ideas on what to try... So I'm not done yet.

Timing:

I hooked a timing light up, and I see the leading and trailing marks, and I understand to look at the leading mark when the light is on the leading wire on the front rotor and the same sort of thing for the trailing. I also understand what to do to adjust each one... I have the shop manual. What I don't understand from the shop manual is the degrees it lists. I don't have it right here, but it lists something like 5 or 20 degrees for a 13B. What does that mean? Do I just disregard that and line up the appropriate mark with the timing needle thing?

Thanks,

Brad
1984 GSL-SE