replaced valve body still had hard shift - replaced trs LP fuse NOW will not shift

Where did you get the valve body from? Was it the whole valve body? Or just the upper valve body? Also with a blown trs lp fuse its going to shift real hard because line pressure will be full pressure all the time and not just full pressure for reverse like it should be. Also was the trs lp fuse blowing before the valve body change? Also you didnt pinch the valve body wire harness underneath the valve body cover did you? What are the exact code numbers that are being set in the computer?

I got it from a company that rebuilds these valve bodies. It was the whole valve body. No it was not blown before the valve body was changed. However, the circuit board (bus plate) inside the (old) valve body which I replaced was fried. The fried circuit was for the solenoid number 1 (line pressure). No wires are pinched. There are no computer codes.

I suspect a wiring or sensor issue but the trs lp fuse has not blown since I replaced it. I have power at both sides of the fuse.

Did you ohms check the line pressure actuator when you replaced the buss plate? I suspect a line pressure actuator from what you have told me so far.

I ohm checked all the solenoids. Range 5.0 - 5.2 ohms.

So did the valve body come with the bad buss plate etc right out of the box?I tried to buy some rebuilt valve bodys and they were all a piece of junk bad line pressure actuator in one.Broke buss plate on another completely bad on another one.How much did you pay for this valve body?

No the bad bus plate was in the original valve body which I replaced. I paid around 150 dollars for the new valve body.

This is the second valve body from this company. Like you, I thought maybe they sent me a bad valve body, so I had them send me a second one. Both acted the same way (continued hard slam). I discovered the blown trs lp fuse after I installed the second valve body.

Alright so now that the fuse for trs lp is good the car wont shift it stays in 1st gear and wont shift?Also when the fuse was blown it shifted thru every gear just really hard?Do you have any codes in the computer?If so what are the exact code numbers not the code descriptions.Also do you have a transmission pressure tester gauge set?

Yes, it stays in first gear and is very slow moving even when the engine is revved very high. Yes, when the fuse was blown it shifted thru every gear. It would start out shifting hard but after 30 miles it was shifting without banging. However, once the car was turned off it would shift hard again. There are no codes in the computer. I do not have a transmission pressure gauge set.

You say the car is slow moving even when the car is reved high?Is the transmission slipping in first gear?If you pull the trs lp fuse out will it shift thru the gears?Your going to need to get a transmission pressure gauge tester set.

correct - slow moving even when it is revved high, but that is with the good fuse. If I pull the fuse the car goes thru every gear, but it shifts hard. I'm thinking its the wiring???? I'm going to go thru the wiring this weekend - something is blowing that fuse.

Is the wiring loom to the transmission pinched under the valve body cover?Also is there a delay in reverse with a good fuse in place?

no - no pinch under valve body. No reverse at all with good fuse in place.

Then you have a pressure issue and when the fuse is out the transmission defaults to max line pressure.The actuators are electrically off meaning it takes power to turn them off.when you pull the fuse the line pressure actuator opens and allows max line pressure.So the line pressure actuator fuse keeps blowing?The line pressure actuator ohms out to specs and the actuator buss plate isnt shorted out?You didnt over tighten the transmission connector did you?

No, it has only blown once. It has not blown after being replaced. The ohms is 5.1 ohms. This is a new valve body so I do not know about the buss plate. Is there a spec (torque) for the transmission connector?

Do you think it could be the wiring harness? I plan on going tomorrow and getting a manual with the engine harness wiring diagram.

If you pull the line pressure fuse and it shifts and the fuse doesnt blow you have low line pressure in the transmission.Sounds like you got a bad valve body.We need to do a high low line pressure test You will have to get a transmission pressure tester set.You want me to recomend one for you?I have a nice otc one that was under 70 dollars.Those rebuilt valve bodys are garbage i went thru a bunch of bad ones.Where did you get it?Do you have link to it?

I do not understand your sentence: If you pull the line pressure fuse and it shifts and the fuse doesnt blow you have low line pressure in the transmission.

What is the point of the high/low pressure test?

You said you have no reverse with the line pressure fuse in reverse needs full line pressure which would be a min of 175psi.If you have no reverse that means the pressure is pretty low.So if its bellow 175 psi when its supposed to be 175psi and above then when you put it in drive its supposed to about 130psi.So if the pressure is skewed that much then there wont be enough pressure for the foward gears to shift and not slip.The higher the gear it goes 2nd 3rd and 4th the more dependent on the correct pressure it is.Heres what you have to know about what i was saying about the fuse.If there is power to the line pressure actuator its turned off meaning the pressure is reduced.If there is no power to it like when you pull the fuse it will open up and allow full line pressure to the transmission as much as the pressure regulator in the valve body can supply.It sounds like the pressure regulator is worn and sticking and not allowing enough pressure to supply the transmission to shift properly.I was reading about the valve body you got they take a used valve body take it apart clean it up inspect it.Then ohms check the actuators and install a new spacer plater and spacer plate gaskets.So doesnt sound like they did much as far as rebuilding it.I rebuilt the valve body on my 1999 saturn SL2 and i took it all apart cleaned it up bored out the pressure regulator bore.Installed the sonnax pressure regulator sleeve the sonnax pressure regulator the sonnax pressure regulator spring.Also installed the sonnax boost valve now thats rebuilding the valve body.As far as the high low pressure test you install a transmission pressure gauge on the transmission.Then start the car let it idle till you get to normal operating temp.Then see what the pressure reads at idle should be around 60psi.Then pull the line pressure fuse should be over 175psi.Then put the fuse back in and turn the engine off and then restart the engine.Then put the transmission in drive the pressure should read about 130psi.Then put the car in reverse the pressure should read over 175psi.Those cleaned up and new gasket valve bodies are junk i tried getting some of those so called rebuilt valve bodys and got one bad one after another.Has the car ever shifted since you put this valve body in you bought?

The point of the high low pressure test is to check how your pressure regulator in the valve body the pump in the transmission and line pressure actuator is working.

I talked to the company that I bought the valve body from and they feel the problem is in the transmission itself. The tech. from there company said that within the transmission there are friction plated and bands and that mostly likely one of those pieces has broken due to the slamming. He said that they inspect the valve body and do not rebuilt ones that would required a sleeve. I asked it they line test the valve body and he said no.

Does his diagnoses make sense to you?

Should I take the car to a transmission shop and hope they give me an honest answer?

What the company said doesnt make sense because if something was broken then when you pulled the line pressure fuse the car still wouldnt shift because it would still be broken.So the company never tests the valve body as a whol assembly?

I agree with you. No they never tested the valve body as a whole assembly (I assume you mean shifting under pressure). They told me that they do not rebuild valve bodies that need a sleeve. They inspect and clean the valve body and replace anything that is not within spec.

How involved is a line pressure test. Where and how is the tester connected. Do I have to have wheels off the ground so the car can shift to perform the test. If you could give me details I would appreciate it.

You dont move the car to check the pressures.You hook the gauge up where the transmission temp sensor screws in right next to the tranmission filter.Then warm the car up to normal operating temp.Then see what the pressure reads at idle then what it reads at idle with the line pressure fuse pulled at idle.Then put the fuse back in and shut the car the car back off.Then restart the car and check the pressure in reverse then check the pressure in drive.Its really easy to do.Heres the link to the pressure tester i have its really nice.

Here are my measurements. I could not get a pressure tester so I used an oil pressure gauge that I had that goes to 100 psi. This is the type of oil gauge you would normally install inside the car when you do not have an oil pressure gauge.


Start the car let it idle till you get to normal operating temp.
Then see what the pressure reads at idle should be around 60psi. - My reading 74 psi
Then pull the line pressure fuse should be over 175psi. - My reading Over 100 psi (pegged my gauge)
Then put the fuse back in and turn the engine off and then restart the engine.
Then put the transmission in drive the pressure should read about 130psi. - My reading 74 psi
Then put the car in reverse the pressure should read over 175psi. - My reading 74 psi

Without the TRS LP fuse all gears including park/neutral read over 100 psi (pegged my gauge)

What do you think?

I can see why you dont have reverse and wont shift your pressures are skewed really low from what they should be.Since the gauge pegs when you pull the line pressure fuse tells me your line pressure actuator works.But what we cant see is what your actual max line pressure is from the transmission pump.We know it will shift and go into reverse but thats all we know.We really need to know what the actual max pump pressure is because if it was on the low side it skew the pressures low for the forward gears and reverse.That way we could prove it was a bad valve body.So is there any warranty on the valve body?Or are they in total denial there is a problem with and it and just trying to blame it on your transmission?Did it ever shift correctly when you replaced the valve body with the one you have on the transmission now?

I bought a valve body from a different source and now I am getting different results.

This valve body has a sonnax sleeve.

I am not getting the pressures you specified previously. Using my 100 psi gauge I get the following readings.

p - 44 psi
r - 41 psi
n - 25 psi
d - 39 psi
3 - 39 psi
2 - 39 psi

Randomly (at least twice I had a park pressure of 110 psi and a reverse pressure of 98 psi)

When I pulled the TRS LP fuse I read the following pressures.

p - 68 psi
r - 62 psi
n - 41 psi
d - 48 psi
3 - 48 psi
2 - 48 psi

As you may remember with the previous valve bodies I would peg the gauge when in reverse.

Give me the link to the new valve body you bought.This new valve body sounds worse the the first one you bought.Did you get a transmission gauge set yet?

No I have not purchased a transmission gauge set.

Do you know where to get a guaranteed good valve body?

Based on our previous discussions I believe that when you pull the trs lp fuse you will always get a reverse slam. Is this true?

Do you still have the first valve body you bought?If so do you plan on keeping it?

No, I do not have the first valve body - I did get a refund, then I purchased this one.

I really dont know where to get a good rebuilt valve body i went thru the same issue you had getting one bad valve body after another.Thats why when i found a good deal on ebay for the sonnax tools to rebuild the S model valve bodies i bought it.Got the sonnax sure cure kit and rebuilt them myself and they came out working better then any of the factory new or rebuilt saturn ones i have installed.So was the only problem with the oringal valve body you replaced a bad line pressure actuator that damaged the buss connector plate?Before that the transmission shifted good?How many miles on the car?

Correct, that is what I replaced on the original valve body. I do not know the exact history of the car but I was told that it had the hard shift problem for at least a couple of months, then it was parked for a year. The car has 126,000 miles.

I was working on the car again today and have the following update. I installed a new vehicle speed sensor just to make sure it was not the problem and it wasn't. I also measured all the actuators ohms and here they are.

A/B Third - 4.6 ohms
C/D Fourth - 4.8 ohms
E/K TCC - 4.7 ohms
J/H Second - 4.9 ohms
G/F Line - 5.1 ohms

How important is it that they are within one ohm of each other?

With the TRS LP fuse installed the car will shift into reverse with about third gas pedal applied. Goes into drive but will not shift into second or any other gear.

With TRS LP fuse removed the car will hard shift into reverse. Shifts ok into drive, hard shift into 2nd, hard shift into 3rd and shift ok into 4th. I did not have the pressure gauge attached so I do not know pressures.

I am going to buy a pressure tester that goes to 300 psi so I can get an accurate reading.

The person who sold me the last valve body also sent me a service manual and according to it, my problem comes down to three problems.

1 - Pump
2/3 - Pressure regulator and/or line pressure actuator.

Based upon the ohms reading do you think it could be an actuator problem? What are you thoughts with the pump?

One more thing. According to the shop manual the transmission fluid should be either Dexron II or Dexron III. Autozone told me to put in Castrol Import Multi-Vehicle. It is primarily for import cars, however on the back it reads:
Also meets requirements for: General Motors - Dexron III H and prior. Could this be the problem?

I always use the castrol high mileage transmission fluid for the dextron 3 fluid in all my saturn S model transmissions i service and it works great. That is the fluid i recomend for your transmission.We need to see the actual pressure like i have been saying so we can see what the pressure is with the fuse out and reving the engine up to about 2,000-2,500 rpm to test the pump. I highly doubt you have a bad pump i seen very few fail unless some debris in the transmission took it out.So where is the oringal valve body? You said you repaired it?

It is sitting in a box in my garage. Yes, I replaced the line actuator with a brand new one (GM) part. I also replaced the buss plate with a brand new one (GM) part.

Did you ever try to install it after the repair and see how it shifted?Also what is the part number for the buss plate?I have been having trouble finding one.

When I repaired the original valve body I took it for a test drive and it hard shifted but I may of had a blown trs lp fuse. I cannot remember ever test driving the car with the original valve body when I know the trs lp fuse was good.

I will have to look for the buss plate part number.

Lets try the oringal valve body and see how that works and give it time for the transmissions adaptives to relearn.If you could get me the buss plate part number i would be greatful.

buss plate part number 21002828

As far as the original valve body. I did reinstall it when there was a good trs lp fuse but only did a garage test. If I am remembering correctly it would not go into reverse. I will put it in again and test it.

Sounds like you should have stuck with the oringal one keep me posted?

Here are my readings with a 300 psi gauge.

p - 70 psi
r - 65 psi
n - 40 psi
d - 65 psi
3 - 65 psi
2 - 65 psi

When I pulled the TRS LP fuse I read the following pressures.

p - 125 psi
r - 285 psi
n - 90 psi
d - 285 psi
3 - 285 psi
2 - 285 psi

Based upon these reading I believe that my pump is good.

So am I back to it being the valve body.

NOTE:

After taking the readings I put the car into Park and my 300 psi gauge broke (cheap China crap), so I cannot test with the original valve body until I get a replacement.

So these readings are with the new sonnax upgraded valve body you bought?The pump is good from the readings your getting.I told you to get one like mine i have used mine many times and has always worked great.Its not super expensive but its a quality gauge set.