Hello All, hope you had a great Christmas. I am up against an issue I have not yet solved.
First, the Jeep is a TJ, 1999 Wrangler, 2.5L 5 Speed manual with BF Goodrich off road tires.
History, 3 years ago we rebuilt the entire engine, had to replace the block due to a piston fracture, factory defect the skirts fell off and a rod went through the cylinder wall at 135,000 miles. Rebuilt the engine, new clutch, changed all fluids, fixed the brakes. Repaired the rear Differential, all the ring gear bolts fell off? Odd problem.
After all the repairs this rig ran great to 172,000 miles. Passed smog clean had great power for a little engine. MPG 16 city and close to 20 on hwy. It did not burn any oil between oil changes at 3,000 miles.
Now, it started running rough and hard to start then quickly went to a no start condition.
It has battery, it will turn over just fine but will not start.
Compression checked, 140 pounds pretty even on all 4 cylinders.
Fuel Pressure checked to be at 48 pounds on my gauge.
Spark? This is an odd one, I sprayed ether, (starting fluid) into the throttle body, not even a pop. Should have ignited really hard but not even a pop.
So I tell myself it is a no Spark issue. Pull the plugs, all are fouled and a little brown. As good as it ran I thought they would all be near white in color.
I cleaned them all, hit them with a propane torch to make sure they were dry. I also pointed my torch into each cylinder. One at a time they all showed me where the ether had landed. They popped and blue flame jumped out of each hole and burned out.
OK, I think now I have it, plugs were fouled. I put each plug on its wire, grounded the plug and turned the engine over. Each Plug had great spark on its own wire,
So I think, all 4 plugs are sparking, all 4 plug wires are good, distributor must be working?, Crank Sensor must be working, I put all the plugs back in and put a little gasoline on the throttle body butterfly and tried to start the engine.
Nothing other than one single pop out the exhaust.
Pulled the plugs, they are all wet and fouled again. Dried them once again, verified spark and reinstalled them.
Sprayed a little ether and turned the key. Again, one weak pop out the exhaust and no attempt to actually start, even on ether.
So I decide something is bad wrong. I plug my inova code reader into the OBD2 port. It lights up and starts checking for a connection. Says it cannot connect to this protocol? I have tried several times, my good code reader will not connect.
I check. The OBD port has a strong 12 V at the #16 port. #4 port has good ground. #3 has 2.48V, #6 has 4.258V, #7 is dead, #7 is fed by a red wire and I understand it should have a voltage reading I need to trace this wire.
I did test the Crankshaft sensor separately just to verify it is good, I checked the wires feeding the crankshaft sensor to the computer and they tested good.
I had the thought that maybe I picked up a bad load of fuel with lots of water in it gas tank is full. I thought that the water would kill my spark plugs and would not ignite.
I unplugged all 4 injectors cleaned all 4 plugs and did the fire in the cylinders again. Put fresh gas in the throttle body and turned it over. It did pop 2 or 3 times but would not fire. I added a little more and it no longer tried to start. Pulled plugs, they are wet again so I had to clean them once more.
Plugs were new with this engine and are iridiums, they spark when clean but not when wet these plugs should last 200,000 miles and these are at 35,000.
I need to get this running and I am stumped.
Right now I do not know if the code reader would have worked when the engine was running well. Last time I hooked it up was a long time ago and all was fine.
I plan to try and trace why the Red wire feed to #7 port on the OBD2 is dead.
One more thing that may be very important: When this first started I guessed the computer or ECM /. PCM might be at fault. I took it off the car and water dripped out, I opened it up and a fair amount of water dripped out. I said AH HA, I found the issue. Sent the PCM in for a rebuild.
They sent it back to me with a nice note saying they tested this unit and it has no issues so they returned my money? I would have paid and never known any better but they said it was fine so I reinstalled and the same unit is still in this car.
I have left out some of the details but this is what I am working on. I am hoping someone says we have seen this 100 times and you need to fix X, whatever x is.
Since the cylinders were wet with fuel I assume the camshaft position sensor is working and I have read it only affects fuel delivery, since this engine would not run on starting fluid I am not sure where to go next.
If the spark is so far off that it is sparking on the exhaust stroke that may explain the lack of start while I have spark but how could that happen?
Thanks and I hope I at least provided some entertainment for you.
Mark
First, the Jeep is a TJ, 1999 Wrangler, 2.5L 5 Speed manual with BF Goodrich off road tires.
History, 3 years ago we rebuilt the entire engine, had to replace the block due to a piston fracture, factory defect the skirts fell off and a rod went through the cylinder wall at 135,000 miles. Rebuilt the engine, new clutch, changed all fluids, fixed the brakes. Repaired the rear Differential, all the ring gear bolts fell off? Odd problem.
After all the repairs this rig ran great to 172,000 miles. Passed smog clean had great power for a little engine. MPG 16 city and close to 20 on hwy. It did not burn any oil between oil changes at 3,000 miles.
Now, it started running rough and hard to start then quickly went to a no start condition.
It has battery, it will turn over just fine but will not start.
Compression checked, 140 pounds pretty even on all 4 cylinders.
Fuel Pressure checked to be at 48 pounds on my gauge.
Spark? This is an odd one, I sprayed ether, (starting fluid) into the throttle body, not even a pop. Should have ignited really hard but not even a pop.
So I tell myself it is a no Spark issue. Pull the plugs, all are fouled and a little brown. As good as it ran I thought they would all be near white in color.
I cleaned them all, hit them with a propane torch to make sure they were dry. I also pointed my torch into each cylinder. One at a time they all showed me where the ether had landed. They popped and blue flame jumped out of each hole and burned out.
OK, I think now I have it, plugs were fouled. I put each plug on its wire, grounded the plug and turned the engine over. Each Plug had great spark on its own wire,
So I think, all 4 plugs are sparking, all 4 plug wires are good, distributor must be working?, Crank Sensor must be working, I put all the plugs back in and put a little gasoline on the throttle body butterfly and tried to start the engine.
Nothing other than one single pop out the exhaust.
Pulled the plugs, they are all wet and fouled again. Dried them once again, verified spark and reinstalled them.
Sprayed a little ether and turned the key. Again, one weak pop out the exhaust and no attempt to actually start, even on ether.
So I decide something is bad wrong. I plug my inova code reader into the OBD2 port. It lights up and starts checking for a connection. Says it cannot connect to this protocol? I have tried several times, my good code reader will not connect.
I check. The OBD port has a strong 12 V at the #16 port. #4 port has good ground. #3 has 2.48V, #6 has 4.258V, #7 is dead, #7 is fed by a red wire and I understand it should have a voltage reading I need to trace this wire.
I did test the Crankshaft sensor separately just to verify it is good, I checked the wires feeding the crankshaft sensor to the computer and they tested good.
I had the thought that maybe I picked up a bad load of fuel with lots of water in it gas tank is full. I thought that the water would kill my spark plugs and would not ignite.
I unplugged all 4 injectors cleaned all 4 plugs and did the fire in the cylinders again. Put fresh gas in the throttle body and turned it over. It did pop 2 or 3 times but would not fire. I added a little more and it no longer tried to start. Pulled plugs, they are wet again so I had to clean them once more.
Plugs were new with this engine and are iridiums, they spark when clean but not when wet these plugs should last 200,000 miles and these are at 35,000.
I need to get this running and I am stumped.
Right now I do not know if the code reader would have worked when the engine was running well. Last time I hooked it up was a long time ago and all was fine.
I plan to try and trace why the Red wire feed to #7 port on the OBD2 is dead.
One more thing that may be very important: When this first started I guessed the computer or ECM /. PCM might be at fault. I took it off the car and water dripped out, I opened it up and a fair amount of water dripped out. I said AH HA, I found the issue. Sent the PCM in for a rebuild.
They sent it back to me with a nice note saying they tested this unit and it has no issues so they returned my money? I would have paid and never known any better but they said it was fine so I reinstalled and the same unit is still in this car.
I have left out some of the details but this is what I am working on. I am hoping someone says we have seen this 100 times and you need to fix X, whatever x is.
Since the cylinders were wet with fuel I assume the camshaft position sensor is working and I have read it only affects fuel delivery, since this engine would not run on starting fluid I am not sure where to go next.
If the spark is so far off that it is sparking on the exhaust stroke that may explain the lack of start while I have spark but how could that happen?
Thanks and I hope I at least provided some entertainment for you.
Mark
