Need some help on a problem that has me stumped. My '88 Ranger 4x4 2.9L V6 is only firing on 5 cylinders. #3 is not firing. I checked for spark and it is getting it and when I pulled the plug to put in a new on it was dripping with gas so it's getting fuel, maybe too much. I put my thumb on the plug hole it had my wife crank it over and it knocked my thumb off so I figure it has good enough compression to fire anyways. So that's the story. Any thoughts would be greatly appreciated.
03-01-2005, 07:45 AM
If its getting spark and gas you would think it would fire. It maybe the spark plug wire is shorting and not getting the right voltage to that cylinder. If it has a distributer that might be the cause also
03-01-2005, 09:59 AM
Agree.Bad plug wire shorting is often the problem .Replace it with a different one to rule that out.
03-01-2005, 10:52 AM
No expert, but my 91 ranger V6 was getting spark, but had a was missing on at least on cylinder. The miss was load dependent, so that means that simply seeing spark doesn't tell the whole story. I changed plugs, plug wires (a sometimes much over looked item), cap and rotor and it fixed my problems. Your problem could be more involved, but I'd start with the cheap stuff. After that, I'd probably do a "real" compression test.
Hope this helps.
03-01-2005, 11:19 AM
Misfiring under load is usually (can never say always) ingition related.
When it is dark go out and fire it up. Look at the wires and check for arcing. I have to be very dark.
My bet is wires...........
03-01-2005, 01:52 PM
Sometimes a bad vaulve,or cracked head gasket will not allow the compression, it will still 'blow' your thumb off, to build up to the optimin pressure,(135-150psi) could be carbon build up or burned. Another thing, pull the dipstick and smell if gassy could be blow by from rings.
When you do a good compression test, check each one of the cylenders both dry and with a squirt or two of oil- compare and the results should be within 15% of the highest.
03-03-2005, 06:06 AM
OK. I switched a different wire in the place of the one on the dead cylinder. It is still not firing on number 3. So I guess when it warms up a bit I'll check the compression. Any other thoughts?
03-03-2005, 10:06 AM
A local dealership charges me $25.00 for a diagnostic and estimate of repairs.
Well worth it! I take the diagonstic and use it to repair it myself.
Throwing parts at a problem can esscalate $$ pretty fast.
Just a thought......
03-03-2005, 10:34 AM
Have you looked at the distributor and rotor yet? Switching a wire doesn't isolate the other components upstream. Also, I don't think you need to wait until it gets warmer to do the compression test. When cold, you may not get the absolute proper pressure, but you can certainly get a good relative measure and compare with measurements on the other five. It sure sounds ignition or compression related, but again, I'm not an expert.
I also agree with cadetman that a diagnostic may be in order, however, I'd try the above two items first. I recently had to pay to get a computer diagnostic, but around here it was much more than $25 - more like $80.
03-03-2005, 01:26 PM
Shop for a diagnostic.......... it should not take more than 1/2 hour shop time. At that time I was Service Manager and we had a $52.00/hr flat rate.
A good diagnostic is more than a computer reading. We hoisted it and checked brakes, exhaust, etc. Not only did it bring attention to problem areas, generated income, it provided a service to the customer. We welcomed Do It Yourselfer's cuz they often wandered over to the parts dept.
03-04-2005, 05:29 AM
Astrobee: It's because I am a sissy. It has nothing to do with what I think about the motor. I HATE being cold. [img]smile.gif[/img]
I probably will limp it into the shop. Might even have them fix it, depends on how lazy I am being. Of course I have a new motor for it so I might just say to heck with it and change it out.
03-04-2005, 02:54 PM
$25 diagnostic...$80 diagnostic...I wish. My Powerstroke diesel doesn't break often, but when it does the first thing the local dealer does is a $125 diagnostic...and I've checked...it's standard at all Ford dealers.
03-04-2005, 03:17 PM
I hear you Bubbabod. I get spanked on my 6.5 diesel as well. Not $125 though. Labor rates are $10 to $20 and hour less in this area than metro.
03-04-2005, 05:02 PM
LUV MY V-10.
03-04-2005, 09:26 PM
I don't love spending $65 to fill mine up every week. My '99 V10 got better gas mileage than my '03.
03-05-2005, 05:10 AM
My four cylinder keeps looking better and better!
03-05-2005, 05:48 AM
My restored 1980 VW Turbo Diesel gets 51 mpg.......
I am running it on used french fry grease. I use the process of estrification to convert the grease to "biodiesel". Runs much cleaner and seriously, there is the faint smell of french fries near the exhaust.
I grin wildly as I buzz by the gas station.
03-05-2005, 06:25 AM
I'm inclined to agree that it's electrical in nature. Since you switched the wire and still have the problem you have eliminated the wire as the culprit. You still have the possibility of
1. Bad plug- cracked ceramic etc..
2. Dist cap/rotor problem.
You can eliminate the plug by switching plugs out and see if the miss moves with the old plug.
You can eliminate the dist cap/rotor by carefully identifying and moving all plug wires one space on the dist cap (don't just yank them all off, do it one at a time). Do this by moving them one space in the direction of rotation (pop the cap, crank and observe direction). If the miss moves to the new cyl, the dist cap/rotor is your culprit. If the miss stays home at #3.....it ain't electrical and is fixing to get somewhat more expensive.
Diagnostics are a great tool- but I'm tight and only use them as a last resort.
Now where is that big shady tree out by the fence.
03-08-2005, 06:08 AM
Cadetman, May I say that you suck? [img]tongue.gif[/img] I have looked and looked and looked for a TDI and all I came up with was an '80 NA diesel. Not that I am complaining about the 47 MPG but I just wish it didn't come with the 54HP. Wanted that 90+HP os the TDI but oh well. What process do you use for your Biodiesel?
I bought a new cap and button so I'll try that and if that doesn't get it then I am swapping motors and saying the heck with it! Thanks all.
03-08-2005, 07:55 AM
transesterification ..... here's a link for now. I have a better one but it is on my laptop. This will give you the info tho....
My first VW diesel was an 81' N/A (non-turbo). It even had A/C. Man when you were going up hill with a load and the A/C on....... Yikes.
I now have an 86' Jetta Turbo Diesel and my 80' VW Pickup that I transplanted a 85' Turbo Diesel into. The pickup has a 15 gallon tank!! On a good day with good fuel that gives a nearly 800 mile range. And it goes like a bat out of hell (for a little diesel that is).
I get my grease from 2 major franchise fast food joints in town. I provide plastic 55 gallon barrels and they fill them up. I prefer them because they only fry french fries in the oil I collect (cleaner and my exhaust smells so good!).
It is a bit of a pain to produce so I do it in 2 barrel batches (100 gallons) thank goodness I don't have to do it but a few times a year.
Probably more info than you wanted but I tend to wax on about this........