rovering
03-03-2010, 08:57 AM
1st time poster... longtime listener. :p I am my Rovers keeper.;)
I've got a 1996 Discovery SD 4.0L GEMS auto (I also run premium gas and do regular servicing on her). I've been having an issue with it, that appears to be getting worse now, and it's driving me mad!:sly:
Around town, and speeds under 45 mph, she drives just fine. Once you get her up to 50 - 65 mph, and are just driving a mix of flats and very mild incline/declines on the highway, she starts up with the shutter or surging thing. It's very annoying. If I drop her down into 3rd (auto box), and of coarse the rpms jump up to 2800-3000, it appears to go away. As soon as it's put back into 4th, she starts bucking again. It's erratic, meaning not consistant like the ticking of a clock, and some surges are a little more felt that others.
A few months ago, it would only happen a few times here and there on a drive on the highway. Now, it's like every damn time I get her up past 50, she's a bucking fool! Ugh!!!:mad:
It's not the fuel pump or fuel filter (all new). I'm thinking it's not that VSS deal (I removed this and cleaned it as recommended with no change). It's not the MAF meter (that was dealt with last year).
It does not appear to be a fuel issue. I guess it might be a spark issue. I've not changed the plugs/wires yet (but are doubting this will be it as the highway rpm range, that this is occurring, is the same rpm range around town going up/down the hills).
There is no loss of power. The only other issues (and this has been there for the past couple years) is that there is that sticky tappet sound tic tic tic once and awhile (no coolant being used or oil burning) and, after driving around and it's warmed up, 30% of the time when I shut it off, to go into a store for 5-10 minutes maybe, I go to start her up and she turns over, but the idle is really rough and it acts like it wants to die. It doesn't die, but it takes a minute idling to smooth itself out or if rev'd up a few times and idle held above 1500rpm for a few seconds, she smooths out better. I'm also experiencing a rougher idle these past few weeks as well. Almost idles like there's an agressive cam in it. :rolleyes:
It has 140,000 miles on it now. The heads, timing, cam/lifters and have never been done on it either.
Logic tells me these issues are related, but damn if that shuttering/surging/bucking thing doesn't feel like it's the trans.! Yes, it really does feel like it's coming from the trans. I know what a fuel issue feels like and this isn't it (now electrically cutting out might be a different story maybe). Any one ever experience these bucking issues and it turned out to actually be the auto box?
So, and I sure hope I'm going to get some proper tech. advice other than TOSS MORE MONEY AT IT:rolleyes:, what are some areas to check or things that this could be?:thumb-up:
Much thanks to those reading and offering up ideas.:)
I've got a 1996 Discovery SD 4.0L GEMS auto (I also run premium gas and do regular servicing on her). I've been having an issue with it, that appears to be getting worse now, and it's driving me mad!:sly:
Around town, and speeds under 45 mph, she drives just fine. Once you get her up to 50 - 65 mph, and are just driving a mix of flats and very mild incline/declines on the highway, she starts up with the shutter or surging thing. It's very annoying. If I drop her down into 3rd (auto box), and of coarse the rpms jump up to 2800-3000, it appears to go away. As soon as it's put back into 4th, she starts bucking again. It's erratic, meaning not consistant like the ticking of a clock, and some surges are a little more felt that others.
A few months ago, it would only happen a few times here and there on a drive on the highway. Now, it's like every damn time I get her up past 50, she's a bucking fool! Ugh!!!:mad:
It's not the fuel pump or fuel filter (all new). I'm thinking it's not that VSS deal (I removed this and cleaned it as recommended with no change). It's not the MAF meter (that was dealt with last year).
It does not appear to be a fuel issue. I guess it might be a spark issue. I've not changed the plugs/wires yet (but are doubting this will be it as the highway rpm range, that this is occurring, is the same rpm range around town going up/down the hills).
There is no loss of power. The only other issues (and this has been there for the past couple years) is that there is that sticky tappet sound tic tic tic once and awhile (no coolant being used or oil burning) and, after driving around and it's warmed up, 30% of the time when I shut it off, to go into a store for 5-10 minutes maybe, I go to start her up and she turns over, but the idle is really rough and it acts like it wants to die. It doesn't die, but it takes a minute idling to smooth itself out or if rev'd up a few times and idle held above 1500rpm for a few seconds, she smooths out better. I'm also experiencing a rougher idle these past few weeks as well. Almost idles like there's an agressive cam in it. :rolleyes:
It has 140,000 miles on it now. The heads, timing, cam/lifters and have never been done on it either.
Logic tells me these issues are related, but damn if that shuttering/surging/bucking thing doesn't feel like it's the trans.! Yes, it really does feel like it's coming from the trans. I know what a fuel issue feels like and this isn't it (now electrically cutting out might be a different story maybe). Any one ever experience these bucking issues and it turned out to actually be the auto box?
So, and I sure hope I'm going to get some proper tech. advice other than TOSS MORE MONEY AT IT:rolleyes:, what are some areas to check or things that this could be?:thumb-up:
Much thanks to those reading and offering up ideas.:)