lurching down the street

[dmole]

lurching down the street '95 disco

>HELP! The 1st drive of the day has me lurching down the street. As I accelerate, it suddenly loses momentum and sort of coasts, then picks up again. This happens in all gears for several miles (2-3). After a bit this settles down to a minimun amount of lurching just slightly or quits altogether. Had the o2 sensors changed 5 mos. ago and now the check engine light reads left sensor. Lots of gassy smell when I start it up. A bit tough to start. Any comments appreciated.

 

[discomike]

Back to the basics that Moose has been talking about.
How can we help with out model, year, mileage and history???
Mike J.

 

[Sergei]

Well O2 sensor is good thing to change, but it wont cure issue itself, specially if cat is clogged enough to not get thing through anymore. On 95 Disco its good bet for those to be pretty dead (they are dead on my 94... ) Also can be bad plugs/wires/distributor - so fuel isnt getting burned properly going into exhaust, hence all the smell and O2 failure..

I.e as Mike said - more info please

 

[joey]

Since you say you have a '95 Disco I would ask when is the last time you changed you Fuel filter? Last tune up was? Mileage does help here too.

 

[dmole]

'95 disco, bought it w/ history unknown, out of colorado, w/ 130,000 mls. now has 152,000. the fuel filter refuses to budge, been spraying it w/ pb blaster (may have to cut the lines); plugs changed w/in the last year; t-case and both diffs fluid changed last month; o2 sensors changed 5 mos. ago.
how do i get the cats checked? w/ what do i clean the fuel injectors?
thanks to all.

 

[dmole]

can the cat make the o2 sensors go bad?

 

[dmole]

spouce says we've been putting in bk44 every 4-5 mos. for the last year (since we've owned the pig).

 

[Sergei]

- which plugs you got, are they set up properly for Disco..
- do you hear annoying whine/loud buzzing from area of fuel tank when running
- fuel filter is good thing to change.. are you sure you trying to rotate proper nuts in proper
direction?
- cat itself cant get o2 bad, but if something is inside system already, and it back pressurized enough it will fly out into o2 sensor to foul it badly. Not likely, but possible
- how are your ingition wires (still original? replaced? what brand?), and if you taking out spark plugs - are they soaking wet in lovely black grime? Usual cause of o2 dropping dead is when mixture (air und fuel and sometime oil) flying into them.. Plus of course age.

 

[discomike]

44K is good, on your next oil change why not use some engine flush and clean her out a little. may also want to look at doing a throttle induction cleaning, get rid od alot of carbon. You may want to look at your plug wires, they should be pretty tire even if they have been replaced once.
Good luck,
Mike J.

 

[beemer]

trouble shooting 3.9

dmole, pull the vacuum advance hose off the top of the plenum cover and check the advance unit for leaks and travel. Being that old the rubber end fittings on the plastic tube will be loose of split. The vaccum signal is small in volume due to the small orifice in the ****** on the plenum so any leak in the system will absorb the signal. Pull the dizzy cap, rotor and plastic dirt shield to do your testing. Whats the condition of the centrifugal advance? Does it snap back when the rotor is turned? When was the shaft last lubed as well as the advance weight pivots? On my 95 D1 5-speed i'm on the 3rd vacuum unit
at $127 each, found a rebuilder in Oz for $42 that uses better material for the diaphram. Also run the timing at 8-10 degrees unless you have bad gas. Check the centrifugal advance with a timing light with and without vacuum connected. When it acts up again remove plugs and check for color, are they
all even (quick injecter test). Simple tests, if the stealers get you you'll get a big bill. Go test, Carl..........................o&o>.......................................