hi there,
i have a grand voyager 3.3 auto , i have a problem with reverse (the car dont move)[:@], when i rev it up in reverse gear nothing happens, if i rev it up again then the car backfires, i have changed the fluid and filter in the tranny (before i noticed the backfiring) to see if that sorted out the reverse problem, it drives forwards ok ind 3 L.

any ideas anyone????????????????

peter

 

What year is your vehicle? Have you double checked your fluid level to make sure it is where it should be? Not sure if your trans has a vacuum line running to it or not? If it does,you may want to check on that. Good luck!

 

hi gold cruiser thanks for the reply, its a 1997 model, i think it has a vaccum line running to it, also when car is is reverse and i pump the foot brake the revs go up to 1000, as soon as i stop pumping the brake the revs go down to 500 and it has stalledtoo. also i did get the car to move in reverse at high revs (it only moved about 10 metres), i have checked the fluid again and again and added a bit more , when i changed the fluid i got 3 and half litres (UK) out ofit, is this normal? , how would i check/test the vaccum line

thanks peter

 

You mentioned that you changed out the transmission filter and fluid. Didthe no reverse problem start right after you replaced the filter and fluid, or did that problem exist before you replaced the filter and fluid? If there is a vacuum line running to the transmission, I would just check to make sure that it is hooked up, and that the rubber hoses that are used in the line is good and snug, not lose or cracked. Trace that vacuum line from the transmission to the brake booster to see where you are picking up the vacuum from. From what you are saying, it sounds like it may be picking up vacuum from the brake booster. If that is the case, there should be a connection somewhere on the brake booster. Make sure the connections in that area are alsoa snug fit and not lose or cracked or disconnected for that matter. It really sounds like you have a vacuum leak somewhere. One way of checking to see if leakingvacuum is causing your engine to backfireis to disconnected the vacuum line that is running from your brake booster to your intake manifold, orto what ever is connected to at your engine. Now, plug the side that runs to the engine making sure no vacuum is leaking. You can then start your engine and try reving it again and again to see if it still backfires. Make sure that the trans is in the Park position and your hand brake is applied. Do not attempt to put the trans in drive or reverse. We are trying to determine what is causing the engine to backfire at this time. From what you said about the engine reving up when you step on the brakes sounds like a vacuum leak somewhere in the brake system. Try that and see what happens. Let us know the results.

 

hi, i changed the filter and fluid after i lost reverse, after reading posts on here. i will be checking hoses etc today and will update, the weird thing is the car only backfires when im in reverse, i am taking the car to a tranny engineer tomorrow to do tests on it to see what codes are pulled, doing the on off on off on with the key only shows 12 and 55 which is normal when the battrey has been disconnected recently

thanks again
peter

 

Does your engine rev up high at start up, and then drops down to alower rpm when ever you start your engine? My son had a Neon that did that. It turned out to be a defective PCV valve. His intake manifold was sucking in crankcase vapors through the defective PCV valve. His PCV hose ran from his valve cover to the intake manifold. And for some reason, when he stepped on his brake while the engine was running, the engine rpm would rise up like yours is doing. After we replaced the PCV valve the problem went away. I don't recall his engine backfiring at that time, and he certainly did not have any reverse problems. While in Park with the engine running, when you step on the brakes, do you hear like a slight gushing sound of air perhaps leaking from your brake booster? If your brake booster is bad or leaking, you willhear air leaking from it everytime you step on your brakes. I'm thinking if your transmission vacuum linewas tiedinto your brake booster, and if your brake booster was leakingvacuum, that could cause shift problemsand backfires as well. These are things worth checking into anyway. Keep us posted. Good luck!

 

hi again, just checked for the sound of gushing air while engine was running and in parkwhile pumping the brake and didnt hear none, the revs when i start up are about 1250 then drops to just under 1000, not sure if the tranny has a vacuum line, if it does where would it be? what is a pcv valve

 

Send me an email address. I can then send you pictures of what to look for. This is my email address:
Chevy66@hawaii.rr.com. Thank you, Tommy.

 

ok, had scan done on car, the only code what was pulled was 12(battery been disconnected), he tested the tranny and the fault found was input rpms while in reverse were 650 and it should of been 0 (like it was in drive), he tells me its the reverse/low clutch which is the problem and needs total strip down as thats right at the back, i have found a reciept from the previous owner having work done on the tranny, it had seal and gasket kit, (frictions) clutch plate set ,(steels) clutch plate set, dextron 2 atf fluild 7litres , filter, additive lubeguard (which brings fluid up to atf 4) , geartrain and 3rd gear clutch carrier, this was done 2 and half years ago 6000miles, he didnt do a pressure test but would pressure problems be picked up by the scan tools? , is it possible it may be a piston problem what enagages the reverse? and can that be sorted though the side without removing the tranny?, i think the backfiring is related to the tranny somehow, but the brake problem might be something else, thank you gold cruiser for the info very interesting

 

I'm not a trans man and can't help you there. I hope that some of the info I gave you will be of some help. Good luck and be sure to keep us posted with your results.