My 88 pathfinder has 199,000 miles and ran great until one day the engine started loping and the rpms would drop. It gets so bad that I can't accelerate when the pedal is to the floor. I have replaced the cap and rotor, the map sensorand fuel filter. And $1000 later it still does it. Thankful for any and all help.

Did any of that $1000 include getting it on a computer to get read outs of all the operating perimeters? Sometimes that is the only way with the ECM. Some times the cheapest thing to do is pick up parts at a junkyard and keep swapping parts until you find something that makes a difference. Sorry I can't help more.

Yeah definitely should check out the ecm, because that controls the fuel injectors. Had a chevy go bad, and well he had basically made a new car engine wise and got rid of it. Simple ecm swap with a junker and it ran perfectly.

Were you ever able to remedy the problem? My high milage 88 is doing the same thing. The dealer says they're not able to run codes through the ECM and they now want to try a new (filthy expensive) throttle body. All this trial and error is costing me more money with no satisfaction. Help!

My 93 is doing the same. I just paid 500.00 to have the fuel pump replaced since that is what the mechanic said the problem was, but it is still doing the same thing. In fact, it is somewhat worse than it was before.

Try replacing the igniter and coil. Here's what the igniter looks like and costs:

Zip Code Entry at PartsAmerica.com (http://www.partsamerica.com/ProductList.aspx?PartType=194&PTSet=A&SearchFor=Ignition+Module%2fControl+Unit)

Here's what the coil looks like and costs:

Zip Code Entry at PartsAmerica.com (http://www.partsamerica.com/ProductList.aspx?PartType=190&PTSet=A&SearchFor=Coil)

Tried lots of electrical remedies. No luck. Tried replacing parts and sensors on the throttle body. No luck. Finally replaced the entire throttle body with a used ($500) unit. It has run fine ever since. About 30,000 miles. The mechanics at the local Nissan delership did the work, not me, so I really don't know for sure if that's what the real problem was. For all I know they could have discovered a simpler fix in their run-up to the throttle body replacement and then charged me for the TB and labor anyway. The whole repair ran about $1200. I've since found a new mechanic I truly trust and rely on. Right now I have 293,000 miles on my 88 V6 two door Pathy and I attribute most of it to running Mobil 1 oil since the 10,000 mile mark.