Still a miss

[pteepee69]

Got my '94 XLT last Wednesday. So far I have changed air filter, new lower and upper intake gaskets, new valve cover gaskets, new o rings on injectors. Bought a can of MAF cleaner today. Someone give me the list of what else I should be checking.

After changing all of this the RPM at idle increased about 150 or 200, went from about 600-650 to around 800. Can anyone tell me how many ground wires I should have? Might be a bad ground.

 

[nexis]

for the MAF, did you take it appart, and clean it or just spray the cleaner into the tube, because if you just sprayed it in, you may need to take it apart. As far as grounding, from the negative side of the battery there are 4 wires running off, 2 go into a barrel connector and off to the PCM, the big one goes off to the chassis and engine ground, and the 3rd i cant remember. If you still have the stock cables on there, it may be worth it to replace them. Grab a multi-tester and ohm the cables, They are known for corroding from the inside out.

 

[pteepee69]

Last night had to go to Lowes for curtain rod and drapery night with the wife, so I snuck off and got me some security torx heads to open the MAF up. Will clean today.

Both posts are corroded and need cleaning, plan on doing that today also. Also bought a can of CRC throttle body cleaner when I bought the MAF cleaner. Labor of love so I'm in it for the long haul.

 

[pteepee69]

Today I took the MAF apart and cleaned it. The probes or wires were very shiny after cleaning. Also cleaned my battery terminals and throttle body. Went to NAPA and got my battery cables ordered, be in tommorrow. Tried to change my fuel filter but aparently you have to have a disconnect tool, either that or they are stuck but good.

Having fun crawling around in the mud playing with my toy. Tomorrows' list will be cables, and see if my cold/hot air door on my breather is working. Anything else.

 

[nexis]

the tool to do the disconnect is cheap, and worth having. You have 2 options on that one. the cheap one from autozone or any other parts store for about 8 bucks. Or the tools I have fallen in love with. If you have a harbor freight near you, its worth the 15 bucks for them http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=96834

 

[pteepee69]

Took a pair of bolt cutters to my fuel filter today and finally got it changed. Went to town and got a disconnect tool but it still wouldn't come apart. Bolt cutters work good. Also got my cables but after 2 hours messing with the fuel filter I ran out of time for the day. This morning before going to town I took my IAC off and cleaned it. My IAC doesn't have a black cap or valve in the side of it ( like the ones in the thread about cleaning your IAC ). Didn't really notice a difference in the miss while idling but when I drove it this afternoon it didn't seem like the miss was as noticable while driving.

Tomorrow definitely cables.

 

[pteepee69]

Got my cables on today. Noticed where the old one bolts to the block it was able to be moved. When I put the new one on I could see why, the bolt was to long. Added a washer, got her snugged up and when I started my truck I was surprised to see my ABS light go off finally. I had read in another thread where someone else got their light to go off by fixing their ground. One more problem solved. Drive to work tonight I will see how it runs. Also while checking my TPS today ( before changing cables ) the voltage on the wire that is supposed to have 5v only had 4.06v. Would the ground affect this?

 

[nexis]

Yea, a bad ground could be causing that, could also be a bad positive cable. Its amazing what some corroded cables can do.

 

[pteepee69]

Here is what I've done. Replaced upper, lower intake gaskets, valve cover gaskets, injector o-rings, battery cables, cleaned the throttle body & MAF. Checked MAF connector getting a little over 12 volts to the connector. Reading from MAF on signal side at idle ranging from .88 to .90. Check the TPS it reads .98 on signal side, 4.06 on reference side using the connector ground or 5.01 if using the battery negative post. Also cleaned the IAC, voltage to the IAC is 12 volts. Still a miss. HELP!!!

 

[pteepee69]

Tuesday I got a new radiator cap. Old one looked pretty old, figured might have a weak spring. Wednesday I decided to clean MAF again. This time I took the whole assembly off. Removed the sensor from assembly and cleaned both with MAF cleaner. When I was putting the breather tube back on I noticed 3 holes about the size of pencils in the tube. Took some electrical tape and temporary patched them. It helped, but still a miss.

Today I pressure tested the coolant system. Cold and hot. It held good for well over 10 minutes. I did notice a little leak in the weep hole of the water pump(one more thing to replace). Took the coil to AutoZone and had it tested. Tested good. Hooked it back up. Started it up and started pulling plug wires. Seemed to check out. All had noticable change when pulled except #2 there was onlt a slight change when pulled. Checked the resistance on the injector, within range. What now? Somebody......anybody.

 

[pteepee69]

Pulled codes around. Getting cm codes 157, 189 and it flashed another code that I don't see in the Haynes manual code 192.

 

[94explorerEB]

Leaking weep hole? Has it ever been overheated?

 

[nexis]

157 - Mass Air Flow signal is/was low or grounded - MAF
189 - Fuel system was lean at part throttle - Left or Front HO2S - Fuel control
192 - Fuel system was lean at idle - Left or Front HO2S - Fuel control

so somewhere your not getting enough fuel to the engine, or your getting way to much air

check for a vacuum leak first, make sure your not pulling a vacuum leak that would cause all kinds of problems. Once you rule out a nice fat leak, pull the vac line off the fuel pressure regulator, and check the vac line for gas. if there is, then its time to replace the regulator. then head over to auto zone and grab the tester, make sure your fuel rail pressure is within spec. When you are there testing that, make sure to idle the truck, watch the pressure gage, and unplug the vacuum line from the fuel pressure regulator, pressure should jump up 5 to 10 psi at idle, then reconnect and wrap the throttle, again, should jump 5 to 10 psi,
if it fails to raise with pulling the vacuum line, its time to replace the regulator, if it fails to come up with wrapping the throttle, its the fuel pump, and thats a real pain.

 

[Turdle]

Try this
using the wire harness connector near the alternator, apply 12 to each fuel injector, one at a time. You can use your meter probes clamped to the battery for this.
Listen for an audible click on each injector.

 

[pteepee69]

I've done a lot of work since my last post. Replaced water pump to get rid of leak from weep hole, and yes the guy I bought it from had the motor replaced once because it over heated and seized. And then his wife overheated it again after motor replacement. It has been fun. Blown head gasket. Went ahead and replaced heads while it was tore down. New cast heads from King Cylinder Heads. Runs lots better but now I'm getting a rattle when going up an incline. Kinda like a rattle you would get on a distributor motor when the timing is advanced to far. $1500 for a used Explorer. Money spent fixing Explorer.....never ending.