Had a call from some one that needed assitance in troubelshooting there no start issue on 02 explorer.
As a tech, I usally go for the quick basic checks before diving deeper.
Customer was driving the car today and it suddenly died while excellerating from a stop. So he had it towed to his house.
I asked the owner to turn the key on to acc mode. Heard fuel pump prime the fuel line. That is good.
I checked to see if there was fuel comming out of fuel rail, its good. Went to crank the truck. The starting compression sounded off as if, perhaps the belt/chanin timming was off.
Checked cylinders 1 and 2 even/odd banks for compression. Wanted to see if the timming for the cams were off for both banks.
Compression on first stroke for both cyliners was 90 psi aproximatly on first stroke, and 150 on 4th or fifth stroke. So cam timming looked okay. Backprobed the injectors with my fluke DMM and got pulses to the injectors. Can even smell gas odor from tail pipe.
Check the DIS spark on both #1 CYL and #2CYLe both banks. Good spark but I do not know if old plugs would put alot of strain on the DIS coil pack and cause it to partually short like old honda colils so often did.
There was one fuse in the fuse block that was blown. It was a 15 amp fuse. Changed it with another fuse to see if it was a ecm blown fuse. Well, engine still would not start.
So, I am really trying to understand why I can fulfill all the basics and all the basics check out. Question is, can a defective cam sensor upset the timming on the ignition and fire really late?
When craking with my car battery "his battery was getting weak" the engine crank speed was much healthier then customers battery. The engine would some times kick back as if it was a severe advanced ignition timming but would only do it every 10 strokes. Was thinking that it was getting to much fuel in the cylinder and was artificially increasing the compression and would get a diesel like kickback.
Spark plugs are really old but asked customer about issues with fuel economy, slow or long starts and he said there was no issues.
So, what else can be looked at on this truck? I would LOVE to buy a OTC scanner at this time but do not have the budget for it.
Thanks
As a tech, I usally go for the quick basic checks before diving deeper.
Customer was driving the car today and it suddenly died while excellerating from a stop. So he had it towed to his house.
I asked the owner to turn the key on to acc mode. Heard fuel pump prime the fuel line. That is good.
I checked to see if there was fuel comming out of fuel rail, its good. Went to crank the truck. The starting compression sounded off as if, perhaps the belt/chanin timming was off.
Checked cylinders 1 and 2 even/odd banks for compression. Wanted to see if the timming for the cams were off for both banks.
Compression on first stroke for both cyliners was 90 psi aproximatly on first stroke, and 150 on 4th or fifth stroke. So cam timming looked okay. Backprobed the injectors with my fluke DMM and got pulses to the injectors. Can even smell gas odor from tail pipe.
Check the DIS spark on both #1 CYL and #2CYLe both banks. Good spark but I do not know if old plugs would put alot of strain on the DIS coil pack and cause it to partually short like old honda colils so often did.
There was one fuse in the fuse block that was blown. It was a 15 amp fuse. Changed it with another fuse to see if it was a ecm blown fuse. Well, engine still would not start.
So, I am really trying to understand why I can fulfill all the basics and all the basics check out. Question is, can a defective cam sensor upset the timming on the ignition and fire really late?
When craking with my car battery "his battery was getting weak" the engine crank speed was much healthier then customers battery. The engine would some times kick back as if it was a severe advanced ignition timming but would only do it every 10 strokes. Was thinking that it was getting to much fuel in the cylinder and was artificially increasing the compression and would get a diesel like kickback.
Spark plugs are really old but asked customer about issues with fuel economy, slow or long starts and he said there was no issues.
So, what else can be looked at on this truck? I would LOVE to buy a OTC scanner at this time but do not have the budget for it.
Thanks
