vehicle: 1999 LR Disco 2 120k. I have been at school the past several months and my Disco 2 has been driven rarely for the past 2 months, only 50-60 miles usually in city traffic. This week when I took it out for a drive I noticed that it was significantly underpowered and the check engine light was constantly flashing almost the entire drive. Previously I experienced misfiring maybe once a week, but it suddenly got much worse. The codes that I was/am getting are p0300, p0305, p0308, p1300. I figured the most basic and inexpensive attempt at a remedy would be new plugs and also a can of seafoam in the tank and one through the vacuum system via the brake booster. I have noticed a slight improvement in power since the plug replacement, but am still getting almost constant flashing check engine light while driving. The only thing that seems consistent is that the only time the check engine light stops flashing is when driving at a constant rate above 2100 rpm, but I assume that is likely coincidental.

I have about a 650 mile trip home in December after the end of the semester, and once home I would be able to take the car to my trusted mechanic for any further work. So my primary concern is making sure the disco can make the drive back. My only other option would be a finding a trusted independent near Columbia SC. I assume most people will recommend doing new ignition coils/spark plug wires, which is a job I would prefer to do at home, without paying shop labor. Alas, my real question is: If the car is powered sufficiently, even when misfiring, should I still make the 650 mile trip home and do everything there, or will I be causing too much damage with the unburned fuel?

Thanks in advance for the advice.

 

Unplug the MAF and see if it runs better. If so, you need a new MAF.

I had the same issues, flashing check engine light... put new plugs in, same thing. I replaced the MAF and that fixed it. She's been running great ever since.

 

Just took it for a drive with the MAF unpluged, I want to say it ran better, but it might just be the placebo effect. The CE light was still flashing while driving, should that be expected with the MAF unpluged?

 

I think driving it 650 miles with a severe misfire like that sounds like a bad idea. Some newer vehicles are sophisticated enough to shut down the injectors to whichever cylinders are misfiring to prevent converter damage (among other things) from unburned fuel. I don't think these trucks are setup that way though.


Run it at night with the hood up and see if you can spot any arcing from the plug wires shorting out. If it's something as simple as the wires you could probably do it away from home, even though it might not be your first choice.

 

I don't think that it is an issue with the wires at this point, and have checked the wires and plugs at night several times and have not noticed any arching, I think that MAF sensor seems like the most likely culprit and have one on order arriving tomorrow, so hopefully this can be resolved soon.

Can anyone confirm that driving with the MAF disconnected will cause a blinking check engine in itself?

Thanks!

 

It will still throw a check engine light as the system isn't running as it should. Did you buy an OEM MAF? I've read of people buying mafs on here cheap on ebay only for them not to work correctly.

Rockauto has them cheap at like $104

 

Picked up a new OEM Bosch sensor, and am planing on installing in into the original housing. Did you go this route or just buy a new housing and sensor together. I'm trying to figure out house to navigate the 5star security torx needed to remove the sensor from housing. I've read so far that most people either use pliers or use a hacksaw to cut a line and use a flat head screwdriver for removal.

 

I got a new OEM Bosch sensor from rockauto complete with new housing.

 

If MAF doesn't address it, might be the coil packs. I had a 2004 with multiple cylinder misfire codes with one obviously bad wire, but replaced that and plugs to no avail. Ended up solving the problem with coil packs. I considered tackling it myself after reading on here that it could be done without removing the plenum, but with the SAI it was way too tight a job for me in the time I had. Shop replaced them, wasn't cheap, but problem fixed.

 

Visible arcing or not, how old are the plug wires? Unless they are quite new a set of wires is a lot less expensive than new coil packs. And in my experience coil packs fail really, others' experiences notwithstanding.

And please, please stop driving the truck as long as you are getting it flashing SES light. It's flashing S ES means cat-damaging unburned fuel in the exhaust. And for God's sake don't try to drive it 650 miles like that!