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Transmission problem?


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The 3 speed automatic in the '86 Regal I bought last month started acting up on me yesterday. It's real sluggish at takeoff whether I floor it or not and it now shifts a lot harder than it used to. Is there any kind of a quick and easy fix for this problem or does it need a rebuild? The car only has 52K miles on it and less than 5K since 1994. Thanks....

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Ya sure its the tranny?? I blamed the trans on my 2002 Regal. Car was not shifting right, would drop into a lower gear way too often, only to find out that the catalytic converter was plugged. Surprised me.

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Thanks for the tip. I noticed today that it's also sluggish in reverse which caused me to think that it may not be the transmission. Since there are no vehicle inspections or smog tests of any kind here in Kentucky I may have to reevaluate the need for the catalytic converter, if you know what I mean. Converting the car to dual exhaust may be the way to go which should me a little more power plus better gas mileage. Thanks again for the tip.... ;)

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I don't know what kind of trans you have, but the T350s and t400s use a vacuum modulator to control shifts via intake manifold vacuum connection.

It's just a can that pushes into the side of the trans. About $10 at an auto parts store.

I 've had these go bad from time to time and cause similar symptoms you describe.

They can also cause trans fluid to get sucked up into the intake and make lots of smoke!

mike

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I don't know what kind of trans you have, but the T350s and t400s use a vacuum modulator to control shifts via intake manifold vacuum connection.

It's just a can that pushes into the side of the trans. About $10 at an auto parts store.

I 've had these go bad from time to time and cause similar symptoms you describe.

They can also cause trans fluid to get sucked up into the intake and make lots of smoke!

mike

There's no smoke involved so I'm going with the cat people and eliminate that and see what happens. If the problem persists I'll get the little can for $10 and replace that. Thanks....

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I highly suspect the car has a trans from the THM200 family of automatic transmission under it. All "analog" throttle linkage with no vac modulator.

That generation of GM mid-size vehicle never came with a true dual exhaust under it. To do that, as some of the later 1980s IROC-Z Camaros did, you'll need to run the pipes to the clearance section of the trans crossmember and them divide them, side to side. On these cars, what looks like "dual exhaust" is really a "dual outlet" muffler.

Many muffler shops can replace the bead converter under your car with the later-style monolith honeycomb converter, usually for about $100.00 or so. OR . . . you can buy the Walker aftermarket converter from NAPA and then get the appropriate "fit kit" so it'll go under your car with NO modifications, just some time putting it all together. ONLY issue might be that in some cases, there was an A.I.R. pump air pipe which went to the converter, which would have to be dealt with somehow.

Be sure to check the vacuum advance cannister, too, for general principles. Also, when the knock sensor wire grounds, it kills all advance in the distributor. The knock sensor usually in on the side of the block, where a block drain plug previously was.

Just some thoughts,

NTX5467

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I replaced the cat with a piece of exhaust pipe but that didn't solve the problem. I thought it might be the fuel filter so I thought I would try to replace it. That was a BIG mistake. It's inside the carburetor so when I was removing the metal gas line I twisted it which caused a leak. I cut through the gas line with a hacksaw blade because I couldn't get to the other end to remove it because it's below the A/C compressor. I went to the auto parts store and bought a foot long piece of rubber gas line and also a new piece that screws into the carburetor which the gas line attaches to which screws into a bigger piece that the fuel filter is inside of which I also removed. When I tried to reinstall them I screwed the big piece in crooked so now it leaks. The engine runs but gas drips from it so now I'm afraid that I may have ruined the carburetor since the threads inside it are basically stripped. The rubber gas line that I bought was super hard to attach to the carb end too because the top radiator hose mount is about 1/4" directly in front of the carb. So now the car still runs badly and the gas drips from the gas line onto the engine and the threads going into the carb are stripped. I really screwed up a simple fuel filter replacement job and I'm afraid if I take it to the local garage they'll charge me several hundred dollars to fix my fuel line screwup and the car still runs like crap. Any suggestions?

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I would put a new set of spark plug wires on the car first.

Bernie

I replaced the plug wires today and it runs a lot better. I wish I had known that yesterday morning before I came up my brilliant fuel filter replacement idea. I drove it a couple of miles after replacing them and it didn't backfire at all. Now I need to figure out what to do about the gas leak going into the carb. I'm going to take it to the local Chevy-Buick dealer on Tuesday and see if they have any suggestions that won't cost too much. Thanks a lot for the tip, Bernie.... ;)

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Stripping that filter fitting is, unfortunately, rather common. It seems to me that back pressure from the filter's spring easily causes the fitting to go in cross threaded and wham, you're in your boat. The only way I've found to combat this is to put enough pressure on the fitting so that when you have the first !/4 turn you should be able to feel a microscopic in-out looseness in the fitting to the carb. If you have that then easily turn the fitting by hand to tighten till you have 5-5 full turns on it.

But that's water under your bridge right now. I don't think all is lost. I'd recommend going to your local serious parts dealer, and explaining what occured. I believe there is a fitting made for correcting this problem, which essentially re-threads your carb inlet.

Also I would try calling all local yards to see if you can get a replacement carb for the car, in case the aforementioned fix does not work.

I have also head of one person using JB Weld to essentially glue the fitting to the carb. It did work, but may not have had a lasting effect.

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Thanks for the info, John. I guess by "serious" parts dealer you mean NAPA and not Advance? I'll take it apart again and bring them the fitting that's cross-threaded and see if they have another one. If they don't maybe the dealer will. I'd like to try to use my carb before buying one from a junkyard. Thanks again....

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I don't know if this will work for your thread problem but I'll toss it out anyway. When I have stripped a thread one way I have gotten around it is to find a couple of bolts that will fit the thread, take one to the vise and cut a deep groove in two sides, like a self tapping bolt. Here is the tough part, while keeping the bolt straight, turn, tap (because its going to want to follow the last thread patten which is wrong) turn tap... you get the idea. Hopefully, you didn't go all the way down. Once you think you have it run a clean bolt through by hand, do not use a wrench, confirm that it is straight. You will probably have to remove the carb as it doesn't sound like you have a lot of room to work with. Keep it clean, you'll have metal shavings that you don't want going down the carb.

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Thanks for the info, John. I guess by "serious" parts dealer you mean NAPA and not Advance? ....

Advance Auto is okay, So is NAPA. So may be any smaller parts dealer in your area. By serious I mean more than just your average retail outlet selling prepackaged parts on the back wall ( aka Walmart, Kmart, etc. )

BJM, my guess is it's the carb gas inlet that's stripped, not the filter housing/fitting.

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The filter housing is what's stripped. I'm going to try to get another filter housing tomorrow at either NAPA, Advance, or my friendly local Chevy-Buick dealer (all on the same street less than a mile apart). If I can't find one I may try BRH's idea. I'll try to post some pics tomorrow if I haven't gotten it fixed. Thanks again....

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I got the gas line put back on and it doesn't leak (yet). I put some of that teflon tape that plumbers use on the filter housing threads so hopefully that will work. I bought a new piece of fuel line and a tube bender and put it on. The engine idles OK but it still sputters and backfires when I drive it. I don't know what else to do so I called the local garage and he said to bring it in next Tuesday so hopefully it won't cost me more than a couple of hundred dollars for him to fix the problem....

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I took it to a different garage this morning and showed the mechanic what I did. He has seen that cross-threading problem before and said he may be able to put that piece back in correctly so I'm going to drop it off tomorrow night so he can start on it at 7 AM Friday. It was sputtering and backfiring during the 10 mile round trip so hopefully he'll be able to fix both problems fairly inexpensively....

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I decided to give it another try today and I managed to put the housing piece in correctly and tighten it completely so there's no gas dripping at all so that's a huge improvement. It still backfires through the carb when I drive it though. Could that be a result of removing the catalytic converter or cutting the belt off the smog pump? I canceled the appointment at the garage tomorrow because I'm hoping someone here will give me some more ideas as to what is causing it to backfire when I accelerate. Does anyone have any suggestions? :confused:

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I would put a new set of spark plug wires on the car first.

Bernie

Absolutely agree with Bernie. One additional thing is I'd run a thin bead of Dialectric Grease around the inside of each spark plug boot before installation. Put it about a 1/4 inch inside the boots so that when it hits the plugs it will spread out. This ought to impede any desire of the spark to travel down the outside of the plugs to ground.

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I replaced the plug wires last week and it didn't make any difference. I unfortunately don't know how to check the timing. I've seen it done before with the flashing light but I don't have the light and I don't really understand how it works.... :confused:

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Have you replaced the vacuum lines? There's a lot of them in there and the heat from the engine dries them out, after which, vacuum leaks will cause a lot of trouble. I've seen them crack and stay on the fittings and leak, meanwhile they look like they are just fine. I'd replace all of them. Make sure you get the right diameter hoses.

As for timing I ask if you have ever messed with the distributor setting? Ever removed the distributor? If no to both then I'd hold off on the timing. I do not think it is logical that it would slip if it was never messed with and the car used to run good.

As for the timing, a short explanation:

The first cylinder is used to check that the piston is at a certain point in it's rotation when the spark plug circuit is fired. The manufacturer will have a setting in degrees for your car and the light you speak of will have three wires. Two go to the battery to provide the power. The third will clamp over the plug wire on the #1 cylinder.

With the car running and the other conditons met ( unhooking but plugging the vacuum hose to the vacuum advance ) you aim the light to the timing scale found on the engine. You then twist the distributor one way or the other to get the light to fire when the timing mark is opposite the recommended setting on that scale. There is a bit more to it than this but, it is rare that the timing changes out of the blue.

One thing that an cause it to change however is a stretched timing chain. But with 52 K this is one of the last things you should look at.

Check those vacuum hoses first. Low cost and almost guaranteed to need replacement by now anyway.

Edited by JohnD1956 (see edit history)
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Thanks for all the info, John. I haven't replaced any vacuum lines but I did check them and didn't find any that had come off. The only time I have even touched the distributor was when I replaced the plug wires and I don't think I turned it at all. How many feet of vacuum hose should I buy? I'll stop by Advance Auto tomorrow and get some. Also, someone suggested the EGR valve. What is that and where is it located? Thanks again....

Edited by Lebowski (see edit history)
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I was going to suggest that as well. It's a round disc in the intake manifold behind the carb on top of the engine. It has a single vacuum line going to it. You can remove the line and put a golf tee in to plug the line, and see if that helps your driveability.

I have had three of those Olds 307 motors. In two cases the lines were dryrotted and or baked to a crisp. These lines go just about everywhere. If they really look okay, leave them for last. At the back of the intake manifold you'll see a metal line running down the back passengers side of the engine. This is usually connected to the manifold directly with a short piece of rubber hose ( about an inch or so long). This is the line to the vacuum Modulator on the transmission. Under the car on the passengers side attached to the transmission is the other end of that line with a similar looking connection.

I would look this line over very closely. If it has developed a leak then that would directly impact engine performance and transmission shifting.

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Is this the EGR valve in the middle of the first photo? I removed the rubber hose and stuck a screw in it and took the car for a drive when the engine was cold. It ran a lot better until the engine warmed up and then it started backfiring again. Is that any kind of a hint? Also, what is the black thing in the second photo? I couldn't find any kind of metal line going from the intake manifold to the transmission. :confused:

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Is this the EGR valve (see photo)? I took the hose off of it and it still backfires when I accelerate. I drove it down to Advance Auto and the guy there said I should have an OBD-1 test run on it which takes 2.5 hours and costs $225. Is that a good idea? Does anyone have any other suggestions what could be causing the backfiring problem? :confused:

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At this point, there are quite a few things that could cause poor performance and backfiring in that car. Is this your daily driver? If so, if it's in the cards $$$, I'd take it to a shop that can deal with it. I'm sensing that you're about ready to start throwing parts at it, and that is going to be a waste of money. Like John said before, there are about a billion vacuum lines on that thing, any of which can be leaking and leaning the car out. There's an air pump check valve (most likely), but that would probably cause backfiring upon decel. I'm not sure if that car has an OBD-1 system in it, but if it does, I've tested those systems with a paper clip in five minutes. At this point, if it's NOT your daily driver, I'd do a little research, and determine a course of action. My checklist would include #1. vacuum hoses--listen for any whistling underhood. Now would be a time to pick up a vacuum gauge and do a test. #2. timing--AutoZone may rent timing lights. Learn how to use it...now's a good time. #3. Computer system? If it has one, how do I check it? That would tell you (most likely) if you have an EGR issue. #4. This car likely has the emissions QuadraJet, which has probably never been rebuilt. Who knows what kinds of problems this could cause.

If time is not a factor, you can do this and learn some stuff as well. If time is a factor, I feel you're better off enlisting help here.

P.S. Do yourself a favor and buy a Haynes manual for this car. I buy an original shop manual or a Haynes manual for every car I buy.

Edited by Aaron65 (see edit history)
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Thanks for the advice. It is my daily driver but I've got a couple of backup vehicles. I've got an appointment with a local garage for Tuesday morning so I'll report back here that evening and let you guys know what happened....

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Lebowski, The first picture looks like a vacuum break hooked to the choke linkage on the carb. It usually is activated right away to open the choke butterfly when the car is started and before the choke thermostatic spring is heated up. I can't tell what the second picture is. The third picture is the EGR valve.

Two things. I can see in these pictures that you have a lot of original vacuum hoses on the car. The vacuum hose in pict one is cooked and deterioriated on the topside, and the others cannot be far behind.

Also those screws are not blocking the vacuum leaks unless you push them down to the head of the screw. Stop at Dicks sporting goods and get yourself a box of cheap golf tee's to plug those lines and then try driving the car again.

Edited by JohnD1956 (see edit history)
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I bought 30 feet of vacuum hose this morning and spent a couple of hours replacing all of the old ones. I only had a foot and a half of it left when I was done so I guessed pretty well on the length. Unfortunately that was the only thing that I did right because it still backfired when I took it for a drive. I'm done messing around with it and will take it to the auto repair shop on Tuesday. Thanks again for the info....

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I decided to try one more thing. I went to the auto parts store and bought plugs, rotor and cap. I replaced the rotor but I can't get this heavy round thing out of the old cap to put in the new cap. I removed the 4 screws but it won't come out. What is it and how do I remove it? Please reply ASAP because I need to put it back together tonight. Thanks....

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Edited by Lebowski (see edit history)
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I dropped off the car and the mechanic said it might be the timing chain which would cost around $600 to replace. That surprised me since nobody here mentioned that. Is that a realistic possibility? He also said it may be as simple as adjusting the timing so that's what I'm hoping for....

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I can't believe a well maintained, 52,000 mile car needs a new timing gear set

and chain.

Funny how he jumped immediately to the most expensive repair.

He should be starting with a simple timing check, vacuum check, coil check, EGR stuff, etc. before preparing you for a $600 repair. A good mechanic will observe the results of these simple & various diagnostic tests and work towards the actual cause (s) of your backfiring issues.

Go somewhere else and have someone go through the process of elimination; and beware of this guy in my opinion.

Roadmaster75

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Good news. The timing was "way off" and the EGR valve was full of carbon and stuck open which caused a vacuum leak. He set the timing and cleaned the EGR valve and also fixed a gas leak from the gas line that I had installed because he said the clamp was too tight. He said the bill was $90 for that which seems pretty reasonable to me. I told him that I had three new belts in the trunk for the alternator, power steering and A/C and he said he could install them in an hour which would be another $60 so for $150 the car is running good again with all new belts. He said it was a "night and day" difference the way it runs now. I'm going to pick it up in a couple of hours when my wife gets home from work and return the distributor cap and spark plugs that I didn't use to Advance Auto. Thanks to those who offered advice and hopefully the car will be problem free for a while now.... :)

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