Don't know what to do, weird putt putting kinda sound and vibration

[importlvr1883]

I have only found a Haynes manual for the DI's. None for the DII's anywhere. This RAVE CD, can I purchase that anywhere?

 

[99d2]

What happens when you're cruising along at 35mph and floor it? Does is splutter and cough, or does it act about the same as if you just gave it a little throttle?
The Seafoam won't hurt anything and may just solve your problem. Additionally, I would suggest running a quart of ATF in the oil for a 20-30 miles. (Drain a quart of oil shortly before you next oil change, and then top it with ATF....drain the sludge after a few hard miles, change the oil filter, fill with Mobil 1, and you're back in business.)

I have over 100k on a 99d2 that I have owned for almost 8 years. In all that time it has ran strictly on regular gas. I take pride that my engine is original...unlike so many that had heads or entire blocks replaced long before the 100k mark (even with the premium gas). I suppose if I planned on racing across Death Valley in the summer or off-roading in severe heat, I would run premium, but for normal operation, it just doesn't seem necessary.

I know it seems counter intuitive, but higher octane fuel is harder to ignite than low octane fuel. On high compression, high RPM engines, operating at high temps. and on the high edge of ignition advance, premium fuel is needed, otherwise a glowing piece of carbon in the combustion chamber or the ultra-hot edges of the exhaust valve will cause the air-fuel mixture to explode independent of the spark. Just my 2 cents....

 

[joey]

Hmmm straight out of the D2 owners manual

FUEL
Gasoline Premium unleaded gasoline with a CLC or ...........................................
AKI octane rating of 90 or 92 (95 or 96 RON)
is preferred. Lower octane fuel can be used,
but performance and economy may suffer.

 

[ayavner]

Rave

I got the RAVE CD off ebay, best $ i ever spent on the rover.

 

[roverman]

Sounds like valves to me as well. Had the same problem with my '99 RR. Ended up getting a rip off valve job. In hindsight, I believe that a good cleaning was probably all it needed. I'd recommend getting a good fuel injector cleaning, not just a gas tank additive. Try motorvac.com for a service station that has one of their machines maybe. Drive it hard for at least 50 miles after you get it done.

 

[importlvr1883]

To 99D2

When I'm cruising at 35 and floor it, it seems to respond a little better but you can still feel the vibrations. I take the highway to work everyday so I get off the ramp at like 35 or so and then floor it sometimes and it vibrates the whole vehicle. Once I let off the gas and if the truck shifts to a high gear and the rpms drop pretty low, dont feel it anymore. But if the engine stays in the same gear and just gets lower as the vehicle naturally slows down, vibration continues.

So whats the ATF stuff your talking about? Automatic transmission fluid? In with the oil?

 

[joey]

I would use the seafoam before I put ATF in my oil.... if you read the can you can put seafoam in the oil in the same way mentioned, but with a product designed for oil.

ATF will just cause issues.

 

[importlvr1883]

Yeah thats what I was kinda thinkin. Picked up some seafoam yesterday and I'm gonna put it in tomorrow so I will update you guys and let you know how it went.

 

[importlvr1883]

Ok so now only when in drive, not in nuetral, i hear this tapping sound from under the truck when I'm pressing on the gas. But it goes away after a few minutes. Any ideas?

 

[joey]

Quick question have you changed the front drive shaft or at least the U-Joints yet?

When they go bad they will cause all kinds of noise, then the will literally come apart and tear up all kinds of stuff including the transmission.