Caprice Acting up

85 Caprice.
had an engine light. but otherwise ran and shifted fine, maybe a little late on the 1-2 shift, but ok.

guy found a blown fuse for the computer which controls the electronic carburetor. replaced the fuse, now she starts better and runs at much lower rpm, BUT the 1-2 shift comes way early. like around 15 mph and thats too much on the old engine.

anyone have any ideas what i need to change or adjust, or what might be causing the problem, considering it shifts later if the computer isnt working?

 

Mabbe a thought here but I dont think in 85 that computer did much. I would try adjusting the cable from the carb to the tranny first. I just have a hard time buying the computer causing that though. Tell me what tranny is it your yacht has in it?

 

tell me how to tell the difference, i dont think its a turbo400, it may be the next one, i think there was a choice of three that year, but with 7 other cars in the fleet, its hard to keep up with the details.

give me something to look at to tell which trans it is. its paired with a 305 is all i know right now.


i was thinking some other kind of setting since the oddity started after the computer was plugged back in. i know the computer controls the fuel flow into the bowl, and when that was put back into service is when the early shift began. While i was in safe mode with the engine light on, it shifted a little late between 1-2. now its waaaay early.

 

Jase, if all else fails, try the AutoZone Repair Manuals online for the 85.

 

Does it have OD?

 

Yes it does have OD.

 

If it is a OD tranny then it aint a TH400. That is either a 700R4 or a 200R4 tranny. If it is a 200R4 tranny it is goin to be a multipattern bell houding which means it will bot to both Chevy and Olds motors. In the 80's and older GM rods the engines had diffrent bolt patterns. THere is little diffrence in the 700 and the 200 trannys though other than the bellhousing bolts. They both run the same electronis through them. You should still be able to adjust it via the cable that reaces from the carb to the tranny. What is mst likely happeneing is the Kick down cable is not moveing and its stuck. I have had a couple of Olds do me that way.

 

ill check into that when i get a chance. As most here know, im kind of slow on the projects. Been having a bad week too, maybe friday will be a good day and i can get some things done, like see if that cable is stuck, will update.

 

A 200 4R. Be careful messing with the cable on this tranny. It is a balance situation where it balances the engine torque, line pressure and shift feel. They are pretty much self adjusting and if you get the balance out of wack it will damage the tranny. You say the shift points are incorrect....the 200 4R should shift close to the following mph points.... 1-2=15-20, 2-3=25-30, 3-4=40-45. If you are not used to the 200 4R OD tranny it will feel like it shifts too soon under moderate throttle. If it really IS shifting way too soon....have a GOOD, experienced tranny guy that is familiar with the 200 R4 do your adjustment. It's pretty critical on these and it's easy to damage the tranny when done wrong.
There are other factors that can cause a quick shift as well. Inside the tranny. Check the cable first if it really IS shifting too soon.

 

I am glad you came along with that fox I Forgot all about the tranny balance. I think though with this being a Caprice it will hve the 700 in it but to be on the safe side you are right. Be shure to remember that when you take the car out for your test spin dont go hot rodding it up and down the street. Drive it easy. Dont go takeing it out on some 50 mile treck over the mountains and such. but around the block it aint gonna hurt it none.
I have yet to figger Why gm mouted the 200r behind a v8 in the first place. Those Olds 307 HO's used to eat them things alive, the 200r is really what gave the 700r a bad rep to be honest. The 700 had its flaws but the 200r was a POS

 

silver fox, your shift points are correct, except mine is dropping into 2nd around 10mph. For example from a stop, making a left onto a 2 lane road, im in 2nd before i finish my turn. Its lugging the engine bad it used to shift around 20-25 which was almost too late. the 2-3 and 3-od shifts are normal. id like for it to shift into #2 around 18mph


it just seems odd that it was shifting a little late with the fuse blown for the computer, and once that was corrected now it shifts too early. maybe with the fuse blown i was having to run my foot deeper in the throttle who knows. This tranny has approx 197,000 miles on it, and im afraid to take it to the shop. theyll find more wrong with it than i want to hear.

 

Yeah...I hear that, Jase. Hard to find a good, honest tranny guy out there. Emphasis on good. If you know a good tranny guy that you trust, take it to him for a look. If it's toast and money is a problem find yourself a good low mile used one. That may sound like a bad idea but I've seen better luck with used trannies than some of the so called rebuilts around. I respectfully disagree with Big Ugly's assessment of the 2004R tranny being a POS...(if that is what is in your car.) MANY of the track guys use them behind engines putting out 800 HP or more. I had one behind my built 455 in my 88 Electra wagon that was pushing 500 HP and it held up fine with a few tweaks. And I wasn't easy on it. In certain set ups I PREFER the 2004R. The 2004R got a bad rep from its predecessor TH200 tranny that was a weak tranny for low HP engines. I will agree with Big Ug that GM should have put larger rear ends in the 80's Box Wagons and the 700R4 tranny....who knows why GM put the smaller stuff in there? But it works surprisingly well and that tranny can be tweaked to hold tons of HP and it is done everyday. My FEELING, regarding your tranny is that you got used to the late shift and now don't like the original shift points. I could be wrong, but, many people feel that the 2004R lugs...and it does and it is sometimes frustrating. Best advice I have, Jase....is try to do the impossible....find a GOOD tranny guy that you can trust AND that knows 2004R trannies. IF that is what is in your car....could be a 700 but that was rare. In either case....begin your search for a tranny/car guy. Ask around the hot rod shops and the performance shops.

 

Shortly after I got my CP back in '99, I think it was, I thought it would be a good idea to get the transmission flush. It only had about 50K on it, but I'm kind of a preemptive maintenance freak, so I got it done. About a month after that, all of a sudden, I had no reverse. I took it to a transmission place and he said it was shot and had to be totally rebuilt. From what the guy told me, and I had no reason not to believe him, one should never get an old transmission flushed if it was never done before. He said I should've just changed the fluid and not gone for the flush. I think he said something like the gaskets were so old that the pressure of the flush destroyed all of them, hence wrecking the trans.
Live and learn, I guess.

 

There is some truth in that, snoot. Depends on the tranny model, age and the maintenance schedule that was used. Personally, I just change the fluid and filter and never flush them. There are guys that flush the 4L60E tranny, the model on my wagon, all the time but I think I will stick to my method for the reasons you mention.

 

Tranny flushes are the reason tranny shops stay in buisness. My grandfather done a tranny flush on his 2002 silverado and in less than two weeks had in in the shop for a $2400 rebuild. Truck had 60 hou on the clock. I dont like dealing with trannys in used cars cuz sometimes especially on GM if you go for a filter change and new fluid on a car with 100 thou on the clock or more they sometimes will take to slipping. if the tranny had never been serviced.