...said in my best Kansas drawl!

Haven't been around much in recent years. The project '47 truck has been getting only a little attention and the '89 hasn't been driven as much as it used to be. Now, the '89 is being replaced by a '00. So, I'll be browsing around here a bit to get some info, tips, etc. The new one is a '00 ext. cab, 2wd, 4.6. Seems to be in pretty decent shape for having 200k on it. I wasn't really planning to buy it, but at a little over $1000, I couldn't pass it up.

The downside is that the truck does have a motor problem that I won't really get to look into for a couple days. I knew it had a problem, but I figure for the money, I can put a lot of parts into it before it really starts to hurt me. Anyway, it starts without much trouble and idles okay. But it smells really rich, and when you start to move, it acts like it's flooding, before it works through it and starts to run a little better. However, even then, it seems to miss, so that is where I am probably going to start. At its best, it acts like the timing is really retarded. Maybe that should be my first act as it doesn't take much to stick a timing light under the hood.

I guess if there is a common problem that leads to that, I'm all ears. At first, I thought maybe fuel pressure, but since it smells rich, I don't think that's the case. Again, I can check that out. I do know that the previous owner tried replacing a few parts hoping it would fix it. I don't remember what all he said, but I do know the TPS was one of the things. I drove it over to a friend's house in that neighborhood for the night and will get back over there later this week. I do want to at least get it home so I can really look at it.

Dave

 

Ya all might want to check fuel pressure for being excessive or the regulator for dumping gas into the intake.
Might be a stuck open thermostat telling the cylinder head temperature senor to make the fuel rich.
Might be the CHT is faulty.
As far as checking the timing, no dice.
There is no distributor and no calibrated timing marks to test against or adjust.
The only way is with a good scanner.
With a Scanner you can look at live data to see an indication of the issue.
Your into computer control now not the old carb systems.
The old ways are no longer useful.
Good luck.

 

Thanks for the advice. I am actually using this truck as justification for upgrading my diagnostics capabilities! I bought an ELM327 thing off ebay awhile back. I have used it a couple times to read and clear codes using my laptop and some freeware. It was kind of a PITA, though. I am not sure, but I think there is software out there I can download and actually pay for that will do much more, but I hate to spend a lot of money if it won't do what I want. OTOH, it looks like I can buy and Innova 3140, or Actron scanner for about $200 that will do what I want.

I guess I do want to do a bit more research, too. I see youtube videos of laptops in cars being used to do all the diagnostics with nice GUIs and gauges and graphs and stuff. Whereas the handheld units are just going to give me numbers for whatever parameter I want to look at. I am sure that it is largely just preference, but for the same money, does one tend to be better than the other?

 

Stopped by long enough to pull any codes tonight. No codes. Bummer. Ordering an Innova scanner, since I've wanted one for awhile anyway. Not real sure I'll find anything there, but worth looking.

Got to thinking on the way home tonight, though. While I was sitting there in the driveway looking at sensor data, and other info, I noticed that the fuel light was on. Do you suppose it could be as simple as bad gas?

 

btw, I lied about the engine. The seller said it was a 4.6, but it's a 5.4.

 

Ye didn't lie. A lie is when ye intentionally don't tell the truth.

Anyway, hey, how you. Sounds like a good truck to work on.

 

So, if you'll recall, I thought it smelled like it was running rich. So, I got the truck towed home today, so I can really work on it. Pulled the air filter to get to the MAF and as soon as I did, noticed it smelled strongly of fuel. Put the fuel pressure gauge on it, and turned the key on, jumped to 40, then fell off to about 10 in about 3 seconds. Smelled more strongly of fuel. Doing some reading online and it sounds like Fords have a problem with stuck open fuel injectors. My '89 had the opposite problem. Anyway, looks like I get to pull some injectors tonight.


edit: Or it could have been a bad oring in the fuel pressure gauge...

Still smells like a lot of fuel somewhere, IMHO.

 

Monitoring the scanner, I noticed that the O2 sensor, B1S1, never moved from 0.065 V. All the rest bounced around like they should, but averaged well over 0.5 V. So, I put in a new O2 sensor. That's better now. Thought I would take it around the block, but as soon as I put it in reverse to back out of the driveway, the RPM dropped and it died. So, more troubleshooting is in order. But I'm making progress, I think.

 

Okay, the truck drives. Finally. Replaced all the plugs and, man, I don't know how it ran at all, or how somebody could have driven it for as long as it must've been acting up! Found that one plug was eroded to about 0.068". Six plugs were worn to right at 0.088" and one was eroded to 0.098"! Man, what a difference that made. Now, I have a miss that is there all the time, but worse when it shifts into overdrive. So, my gut says that while the coils were working overtime to produce fire, one or more were probably damaged. Next up, which coil(s) to replace. I am concerned that I may not be using my scanner right, though, because through all of that, what I thought should have been misfire info never showed anything. So, that'll be another thread... How to use a scanner.

 

Let me offer some more perspective.
Good coils will fire plug gaps in excess of .100.
Why; these coils are capable of voltages over 40,000 volts but are shunted down by the plug at less than 10,000 volts in a normal firing cylinder.
This tells you the coils can fire very large gaps if the conditions are present and the coil is capable of it's full output.
Next, you ended up with still one faulty coil so replacing the plug won't help much if there is little spark, under difficult conditions such as EGR..
Use your Scanner to get to mode 6, test 53 if it has that ability.
At this monitoring point it will display each cylinder's misfire monitor one at a time by stepping your Scanner control button.
The cylinder with the high counts out of limits is your problem.
Change that cylinder's coil with a known good coil.
This mode 6 test keeps count of misfires long before a code or CEL is set.
All this is just 'sorting out' all the faults when there is more than one present at the same time. It's just recognizing them that has to be realized is the trick..
One caution is don't power down the PCM or you lose the counts until they build back again from driving cycles.
Good luck.

 

Guess I never updated this thread. Before I replaced the plugs, there were no DTCs, and in mode 6, no misfires were detected. In fact, because it was running so badly, I thought it must be something else, or I wasn't looking in the right spot for the mode 6 data. After replacing the plugs, with the truck running much better overall, in an evening of running errands, the SES light came on and I was able to pull a P0302 code. When I looked at the mode 6 data, that DTC was confirmed with cylinder 2 having a very high count. A couple of other cylinders registered 10 misfires, but I'm going to fix the one that is most apparent first and see if there is possibly some effect on the other counts.

Thanks!
Dave

 

Looks like the light at the end of the tunnel is in sight. After replacing the #2 coil, I ended up with a #4 misfire. Replaced that coil, and that seems to have taken care of the misfire issues. I drove the truck on a trip to pick up a bunch of parts and put about 100 miles on it and didn't experience any problems.