I have been nursing a blown head gasket on my 2000 Ranger 3.0L 4x4 for a year or so (blows out coolant into the reservoir). I don't drive it much any more, and have only used it for hauling lumber and other stuff around our farm. I drove it to work a few weeks ago, and when I started it up to come home, it took quite a long time to start. I did not try to drive it for a couple of days, but when I did try, it would not start (cranked but no start). I tried some starting fluid in the intake, but no start. So I figured it had most likely lost compression altogether and was going to need the head gasket replaced. I already had ordered the head gasket kit, and was ready to do it, so I got started later that day. When I got the heads off, there was coolant standing in the two rear drivers side cylinders.

I had the heads reworked (one was cracked and had to be replaced). New valve seat inserts were installed and surfaces planed to level and after about 3 weeks I started putting it back together. I got it finished last week, but now it will not start. Same crank - no start as before the repairs. I hear the fuel pump running when I turn on the key, and there is fuel pressure in the rail. I noticed that I get no RPM indication during cranking and from you tube videos other rangers get RPM during cranking. I replaced the crankshaft sensor, but still no RPM and no start. I tested the coil and the primary winding resistance is .11 ohms on all three coils, while the spec says .5 to 1.1 ohms. Secondary coil is showing 13,800 ohms per spec. I have not checked the spark, but know I need to....I was just trying easy things first (also pretty sure I have none).

Does anything I have done so far give anyone any clues as to the problem? Thanks.

Jerry

 

Welcome to the forum


If you add fuel manually to the intake, i.e. Quick Start(ether), and engine doesn't start then you have no spark, or no compression in ALL 6 cylinders, even with 2 "bad ones" engine would still try to start on the 4 "good ones".

So you have No Spark
After cranking the engine a few times pull out 1 spark plug and see if it is Wet with fuel
If it is dry then Crank sensor could be the problem
If it is Wet then crank sensor is OK
And with 1 spark plug out crank engine and you should hear loud Whoomp on that cylinder's compression stroke, or if you have a compression gauge use it, just to take compression off the table, expected with 5 spark plugs still in is above 140psi

Crank sensor sets base timing for Spark and fuel injection, it is of course, near the crank on front engine cover and reads "gear"/tone wheel on the back side of the crank pulley

Cam sensor, on the 3.0l the Cam sensor can cause a no start, because Cam Synchro unit drives Oil Pump, software programmers added a system shutdown if there is no Cam Sensor pulse, because that could mean no oil pump as well, this was only on a few years, but I think 2000 was one of them.


Your Coil pack tested bad, and it could be, but maybe you read it wrong, you need to use lowest setting on meter.
Coil pack will usually test out .8-1.8
And having all 3 coils in the pack fail at the same time would be an extreme long shot.
Usually one coil in the pack would fail and even that is rare, and would cause misfires not No Start

 

Okay. So I tested the spark in one of the cylinders and confirmed it has spark. Checked fuel rail and it has pressure. So I need to do a compression check, and my fear is some type of damage or wear in the lower engine - possibly timing chain or camshaft. Haynes manual says engine must be pulled to change the timing chain on a 4x4! I will do the compression check tomorrow and see what I have.

I guess the "you tube" reference to cranking rpm should register on the tac appears to be bogus for my truck. In all the years of driving it I never really noticed if rpm registers during cranking or not? Of course, it always started right off before.

Jerry

 

I would do 50/50 test again
Spray gasoline or Quick Start(ether) into the intake and try to start engine
If it starts and dies you have compression and spark(at the right time), but no fuel from injectors

If it doesn't start then you have no spark(at the right time), or no compression

Fuel pressure doesn't mean fuel is getting into cylinders

And spark at the plug doesn't mean it is at the right time
50/50 test is easy and tells you alot

If you have a vacuum gauge you can test for compression while cranking engine, you should see 2"-5" of steady vacuum while cranking, throttle closed, if needle is jumping around then there is a valve timing/compression issue

 

After checking everything again, I found I had the No. 5 and 6 spark plug wires reversed. Still no start. Tried to start with starting fluid...no start and had a huge backfire out the intake. Started checking compression on 5, 6, 1, and 2 and got 90, 85, 75, and 85. But the gauge I have is not ideal and I discovered a leak after I had done these. Fixed the leak and checked 1 and got 115; then checked 2 and got 110. So it does have compression, although a little low. Timing may be suspect with the backfire? I did not have a vacuum gauge handy.

Jerry

 

Coil wiring is
3 4
2 6
1 5
front

or
1 5
2 6
3 4
front

3.0l had coil mounted both directions
1 and 5 can be reversed
as can 2 and 6 or 3 and 4, as each set shares 1 coil on the 3 coil pack

5 and 6 can't be reversed, but that would not cause no start just rough running with 2 cylinders misfiring.


Because of the no start when adding Ether(quick start) your spark is very very weak or happening at the wrong time.
If you can lay your hands on an old style timing light you can check spark timing while cranking engine.

Coil's 4 wire connector should have full 12volts when key is on, battery voltage
So test battery voltage, if it is 12.4volts then coil connector should have 12.2volts to 12.4volts


Could be compression gauge but engine does need above 100psi to start cold

 

Mine is wired now as:
3 4
2 6
1 5
Front

I checked the coil voltage and it was 12.08 vs 12.34 Battery. With ignition off the battery is 12.64 Volts - is it normal to get this much drop, with no load?
I am pretty sure the compression is going to be > 100 on all of the cylinders I have checked (1,2,5,6). I could not get to cylinder 4 with my compression gauge without taking off the ground wire and the fuel line support.

I have not changed the plugs. I know they are at least 3 or 4 years old (they look like new - have only a couple thousand miles). I think I will change them out. I have had lawn mowers with good looking plugs and no start - fire right up after installing a new one. I am starting to think some of them have gone bad. Before the head gasket work, I had noticed that it would start up missing on one or two cylinders and then after 30 seconds or so all would start hitting and it would run fine and start fine until you let it sit for a day or two. I thought that the head gasket was probably leaking water into one or two of the cylinders that was causing this? I am starting to wonder now if I some of the spark plugs are taking a while to warm up and start working (or the water in the cylinders has damaged them)?

Thanks for the help "RonD" - I think I we are making progress (albeit slow).

Jerry

 

Misfires happen with a bad spark plug, you have a no fire at all, no start.

And I assume this just happened overnight/instantly, no slow build up of misfires and poor running for a few weeks earlier


3.0l Vulcan engine runs 9.2:1 compression ratio, which means 165psi would be expected in each cylinder.
Blown head gasket just effects 1 or 2 cylinders on a bank, all 6 are showing lower compression if gauge is correct.
This would mean the cam and crank timing has slipped, so valves are opening and closing out of time with pistons
3.0l uses a timing chain so not likely to "slip", but crank gear or cam gear can shear woodruff keys that hold them in correct position

Longshot but does happen, and that would also cause spark at the wrong time since Crank's main pulley shares that woodruff key and it times spark

I would test compression gauge on another engine, even a lawn mower
Briggs and Stratton L head runs 6:1 ratio so should be just over 100psi, 108psi
OHV head runs 8.5:1 so 150psi

To get expected PSI multiply compression ratio by 18
6 x 18 = 108
8.5 x 18 = 153
9.2 x 18 = 165.6

18 comes from 15psi air pressure at sea level to 2,000ft elevation + 3psi mechanical compression of piston moving up cylinder with valves closed

Gasoline needs to be a warmer vapor to be ignited by a spark, this is why compression is needed in the first place.
100psi is kind of the magic number for cold gasoline, compressing it warms it up and turns enough of it into a vapor that a spark can ignite, the flame of the ignition vaporizes the rest.
Starting fluid(ether) vaporizes at a lower temp which makes it a good cold starting fluid, but it still needs to be warmed up and it still needs a spark to ignite

 

I wanted to follow up on this post with the resolution. SPARK PLUGS!!!! I bought a cheap set of Autolite plugs for $12, just to see if the old plugs were the problem. It fired up immediately with no issues at all. I just felt like I had tested everything until blue in the face and everything I had tested was not finding a problem. Since it did not quit running I became convinced there was nothing mechanically wrong and something had stopped working electrically that had been working before when I last parked it about 6 weeks ago. Since there was spark going to the plugs, I became suspect of the plugs, even though the odds that enough bad plugs were present for it not to run, may have seemed unlikely. This is the second time bad spark plugs have burned me, and I am going to try not to let it happen again. I do need to thank RonD and anyone else on the forum who may have contributed to the this thread. I learned a lot about my truck that I did not know, and so I can take that away from this, and am happy that perseverance has triumphed once again.

Jerry

 

Thanks for the update and the fix that worked

Good Work