I just did a full tuen up on my car ran grret the other day but tongiht i was driving it and i backed outta my grague and noticed Coolant on the ground again i changed the water pump 2 months ago because i thoght it was the waterpump leaking. about 2 weeks after i replacewd the water pump i had coolant on the ground again. Then it stopped and a few weeks later came back went away then just came back again Any ideas whats causing that?

Then i was at a stop light and it was surgeing really bad it would drop to 250 rpm up to a 1000 down to the bottom of the tach then up to 1000 again It also randomly does that as well?

Then when my car is cold in the moring and i drive it my speedo shows im going 0MPH then i shift to second and it shows my speed then is fine the rest of the day til next morning. Also at certin speed s my car bucks back and forth. i posted this on the tranny board got no replies.

If any one can help me that would be GREAT. im Stumped oh i have a 91 RS 3.1 and i replaced the Idle Speed Sensor about a year ago and the surging started tongiht outta no were also there is no SES light.

 

I'd check map... check for vacuum leaks, too. Do you hear a hissing when the engine is running? (lift the hood and listen)

Your VSS may be going out, as your speedo is electronic, IIRC.

Did you torque the water pump bolts down correctly? One probably worked loose. Check those bolts!

 

for the speeedo i would look for a loose conection maybe the shift is moving a loose wire back into contact

the water pump i would check all the bolts as Doward suggested as well as all the hoses,clamps and the over flow tank it may be cracked what are the "random: conditons at wich your car surges ?

i don't know much about v-6s are they fuel injected? you also might want to look at the EGR hope this helps Later

 

Your car recovered from a drop to 250 rpms?? Jesus christ... I don't know any car out there that I've seen that has been able to recover from that severe a cutout....

By Idle Speed Sensor......do you mean the Throttle Position Sensor...or the Idle Air Control valve assembly?

Longshots worth checking...IAC assembly and EGR valve...

So you're leaking coolant when the engine is cold and sitting, and at random intervals? Maybe one of the hoses is splitting or loose. Check your lower radiator hose. Those suckers get ruined easily because they take the most heat and sludge in the radiator. Wait til everything's cold and feel the hose...squeeze it, especially in the middle. If it feels soft and easily flexible/squeezable, it's toast.

The speedometer thing....maybe a malfunctioning Vehicle Speed Sensor? My car, the speedometer didn't work unless I either a) drove the car for anywhere between 5 and 20 minutes, or b)went full throttle a couple times until the needle kicked up. Never did get the problem worked out but I was guessing it was the VSS because when the speedometer worked, it worked fine...but when it didn't, it didn't work whatsoever.

What certain speed is the bucking? I'd bet it's at 40 mph, and the bucking is your torque converter clutch engaging and disengaging as you tip back and forth between 39 and 41. Wiring a manual converter lock switch will solve this problem...possibly a new torque converter clutch solenoid too...but the first is easier. Just remember to turn the switch off during EVERY deceleration and acceleration. Use it ONLY when CRUISING at or ABOVE 40 mph or LIGHTLY accelerating. Anything other than this will cause a lot of stress on the converter. Click here for instructions. It's VERY easy.

Good luck.

 

It looks almsot like its leaking from the top of the waterpump in back its hard to tell where its comming from. Ill probly mess with it later today. I drove my car 40 miles to school today and no problems at all. I almsot want to just replace the timing cover gasket and throw a new timing chain on. I was shocked my car recovefrd when it was surging it felt like it was going to die but then kicked back up. im talking about the IAC is what i replaced. Could it be out of adjustment???

 

I just dont understand why it would leak water sitting still but not when it's driving. Everything is under more stress when it's in motion and heated up. But about the top of the water pump.....maybe it's just installed wrong...I assume there's a gasket for it, maybe that's broken? I don't know...I'm no expert....

 

The thing i dont get is its leaking like it was with the old waterpump. Ive checked hoses the top hose is brand new no coolant in the oil im stumped. And its right in the front of the engine in the middle by the crank is where it pools up on the ground. Today it was perfectly fine no leaks. And wouldnt it over heat if there was a small leak?

 

It will leak standing still becuase there is more presure in the system especialy if it is cold. If it is cold the stat has not opened but the water pump is still moving. The stat causes a blockage which builds up more presure untill it is warm enough for the stat to open, presure drops and the leak stops. This was happening to me after I changed my timing chain.

When I changed the timing chain I apparantly didn't scrap every last bit of gasket off. There was a little pice up top towards the back of the timing cover. Instead of take all of the crap off again and cleaning the surface I just some high temp water resitant RTV type goop designed to be used on the water pump. Let it cure over night and now the leak is gone.

Other possibility is that lower connect for the rad hose has a hiar line crack. Mine has a bunch. This also causes a leak when the engine is cold and presure is higher., but for me it only causes a minor leak no biger then a baseball. So I haven't bother with it.

Hope that helps point you right direction.