hard start,misses,backfires
 

Hello truckers, i have a 87 ranger with the 2.9 engine standard shift. It backfired and stoped running the other day, the code indicated ignition mod. and pip failure. I replaced the ignition coil, ignition mod. pickup coil, plugs and wires. The truck will start now after many turns and when it does fire it runs really bad missing, backfiring throughout rmps. It will not stay running with giving it the gas If i move timing forward it will start quicker but still runs the same. I checked compress. i have 120 on all six. Whats wrong with this thing. Timing belt,stuck valve,fuel injectors? The truck has 100,000 miles on it but previously ran like new. Help

Make sure you have your spark plug wires on in the right order. Did you replace distributor?

My first thought was the timing chain slipped, but if you have that much compression it is unlikely. Try a vacuum guage to see if you have a leak, sticking valves, etc. If the vacuum looks good, my guess would be in the distributor or possibly the new ignition module. Are you sure you didn't cross a couple of the plug wires when you replaced them? The right side is 123, left side 456 starting from the front. Firing order is 142536. Keep us posted.

Yes, double checked wires several times, i did not replace dist. Just did a good visual, will buy vac. guage tomorrow. Forget to tell you i still have a code 14 PIP failure in Continuous memory.Don't knowif that is left from before.

Clear the code by pulling the negative battery cable for 15 minutes and see if it comes back.

Today i took the new iginiton mod. in for testing , it failed so they gave me a new one. I am afraid to put it on until i find out what killed it. The failed module was purchased and installed last week. the truck had only been started a couple of times, running poorly each time. what could be causing the module to fail. does the computer have any thing to do with it, are maybe i just go a bad one ?

I've bought brand spanking new ignition modules and coils that were bad. Don't be afraid to install your new one. Install it, clear codes, and fire it up. Forget the vacuum gage for now. I'm not sure what pip failure is, but often one fault will trigger another. This is where it's nice to have a service manual with a flowchart to guide you. BTW, did you have them test the module that was in it at the time of failure?

BTW, smart move for NOT assuming that the replacement part was good just because it was new.

Thats cowboyBilly, i will install it today, i did have the original one tested it failed and this time i had the new one tested before i walked out of the syore so i know this one is a winner.

Update, I installed the new ignition mod. It runs a little better but still is not drivable, I think i may have a fuel problem or something. I took it out for a drive yesterday and it did fine for the first three blocks but after that it started bucking like a old bull , sputtering and kicking, however it only did that if i pushed the gas. It still runs just fine sitting in one spot. So what do you think?

Oh, by the way, No codes are present since i installed the new mod.

Maybe try a new fuel filter and some injector/carb cleaner. Just a thought. Also, check to see if your air filter is clogged because if the engine isn't getting enough air at higher RPMs it'll cause your engine to stall or run like crap until the RPMs drop back down.

Check the fuel filter. It could be partially clogged which would make the engine idle ok at low fuel demands, and not run at higher demands. Or maybe the fuel is contaminated (water).

i checked the filter, it did not have a cartrige in it. Must have been like that since 89.(thats when i bought it). My fuel pressure is above 10psi at the rail. I put some STP in it and it seem to start running a little better. The Vac. moves between 18 and 20 psi. it still backfires a bit. I think i will pull the valve covers and check the rocker arms.

You should have 35-45psi of fuel pressure at the rail, 10 is not enough.