QuestionQUESTION: hey John,
I just bought a 1998 Land Rover Discovery and I am having a problem. When I drive it long distances it seems to be almost like it's coming out of gear or something, and it will have no power for about 3 or 4 seconds then it will kick in again. It will continue doing this until I park it and let it set for about two hours, and I have no idea what it is.
I appreciate the help,
Derek
ANSWER: Hi Derek,
if its gear shift related, it could be that it needs a linkage adjustment. If its power related, it could be a sensor that overheats or faults out, something like the MAF (mass air flow) or the TPS (throttle position sensor). Its also possible that you may have a sticking exhaust valve(s) problem.
Does it trigger a Check Engine Light fault on your dash?
IF it does, you can go to an Advance Auto parts store (in the US) and they could read off the fault codes that were triggered and trapped. An ODBII code reader will allow you to read these codes and maybe give you a better notion of where the trouble is.
Best of luck,
JohnMc
---------- FOLLOW-UP ----------
QUESTION: Hey John,
Thanks for the advice about going to Advance Auto Parts, I actually went the other day and had someone put the OBDII code reader on my Rover. The code said that it was "multiple cylinder misfire". They told me to replace the plugs and wires, and I had told them that I already did. Then I went to ask another Discovery Owner, and he had told me that it sounded like an oxygen sensor problem, and also said that all four oxygen sensors need to be replaced every 60,000 miles.
I wanted to ask what your opinion on the new situation would be, and yes, after the check engine light was cleared, the engine heated up again and the light promptly came on when the engine lost power.
Thank you so much again for your help,
Derek
Answer****************** Follow up
Hi Derek,
I don't know about replacing the O2 sensors every 60K miles. I've not heard that one before. You may want to have a LR mechanic perform some bench tests to determine which sensor or component is faulted. It could be the MAF, the crank sensor, .... an number of sensors involved in these types of misfires. Could even be your coilpack.
Just in case, check your vacuum hoses and connections. Are you sure the spark plugs and wires meet LR spec and were installed correctly? Sometimes, if the plugs were not installed tight enough, they can come loose and give a similar result. What kind of wires were installed? I swear by Magnecore 8mm - work best with high temp engines like ours.
You'll then have to check your fuel supply and exhaust to make sure both are flowing freely and without obstacles or blockages. How is the state of your exhaust system?
A simple cylinder compression test will tell if you have mechanical troubles instead of electrical. Most local garages should be able to do this (or you can do this).
I wish I could be of more help, but don't start swapping out parts if you don't have to. Most sleezy shops will do this to generate money. If you have to go to a shop that starts doing this, make sure they are willing to reimburse you if the swap does not work. As soon as you make this request, the sleezy shops will start to make excuses.
JohnMc
