pathfinder 4litre v6 petrol with engine management light on,nissan dealer cant diagnose problem?

Question

? its just over 3year old and has done 69,000miles(motorway mileage).now and again between 55 and 75mph it will give a kind of shudder,it actually feels like its on a rough road surface,then it picks up and will continue for maybe 20 miles before doing it again.the management light comes on and stays on.My local nissan dealer (who have serviced it for past 3 year )have had it in 3 times now,the last time being 9 days! First they said it was a lambda sensor problem,then a wiring problem,now they say it is "probably" the cat on the left bank of the exhaust system.They will not guarantee that putting a new one on at £1250 will definitely cure it.They have cancelled the fault on the computer and at the moment there is no light on and its running fine,but i know it will come back after a few miles.Surely if the cat was faulty it would run bad ALL the time? A mechanic friend of mine thinks the engine has an intermittent misfire and it will be throwing unburnt fuel into the exhaust system thus causing the engine management to think the fault is there,does that sound feasible?How on earth do i fix this problem when my main dealer cant help without them guessing at my expense?Any advise would be greatly appreciated,thanks .p,s my mechanic friend says he does not want the job as it will be a nightmare to work on.

Answer 1

There is one thing that will drive Nissan Dealer nuts until they see it happen a couple times. Eventually the ECM engine control module relay will completely fail. That relay is located on the IPDM Intelligent Power Distribution Module.That is near the shorter row of (10)fuses row third from the left 4 relay row. Temporaly Repair is to exchange the rear window defogger realy #4 with #3. IPDM is located on right inner fender and has two rows of (24) fuses. Tell your dealer a friend from Texas has seen your trucks condition and says it normally does not set a check engine light. AS for your cat converter code please check the exhaust 3 bolt flanges for cracking before replacing those converters IN the USA Nissan warranties those for 8 years 80,000 miles

Answer 2

This is one of those problems that can drive a mechanic nuts, the best thing to do is put a scope on it and drive the car with live streaming data and capture the data at the exact time it starts having the problem, if you know for certain that you can reproduce the problem then get the dealer to hook up the scanner and go for a ride. I had one like this once and found out that when the car would make a left turn and speed up as it was going into the straight away it would die, well a dozen mechanics worked on it, replaced the fuel pump and filter dropped the fuel tank cleaned it out all sorts of stuff, the Guy brought the car to me Oh Joy! and I spent an entire day on it so I finally decided to gut the catilitc converter, this was illegal but I'm trying to fix the thing, so when I pulled off the cat on one side I found that the honeycomb had come loose and when it was plugged and when it went around a corner it would plug off the engine and die, once it set for a minute it would start up and go for a while, after gutting the cat I tried to get it to die so I replaced the cat on that side and he never had a problem with it again, but he did not want to pay me for a days wages and the cat either, but finally he did. That was before infared heat sensors that could test the cat if it was working or not, so I can understand your freinds point of view, he would rather keep you as a freind than lose you over a stupid car problem. good luck Don't know much about your systems in your country here in the U.S. we have the systems built in to test and capture data to help diagnose the problem.

Answer 3

I have had a similar problem on my wife's Vauxhall Zafira 2.0L TD. The mil light comes, the car losses power for few seconds then it clears itself and the light goes out. I put a new air flow meter on the car, and this cured it for about a month. Then the problem came back again. I connected a diagnostic laptop to the car while driving to see if any fault codes came up when the mil light was on. I got nothing at all. The car has been doing this for about a year now, and its never got any worse, so I just live with the fault. Modern cars can be such a pain.

Answer 4

go to autozone or a real shop to have it look at dealerships not that great for finding problem never has been and most of time higher in price