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Daniel Wilson
Daniel Wilson,
Category: Medium and Heavy Trucks
Satisfied Customers: 1964
Experience:  Owner at DJ Wilson
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Good afternoon Curtis. I own a used 1999 Genie Z 45/25 boom.

Customer Question

Good afternoon Curtis. I own a used 1999 Genie Z 45/25 boom. It has an up dated wiring harness dated 3 of 2004. I have chased electrical problems with the turret and boom operations. Now I have an engine miss fire I can't correct. The engine is the Ford 4 cyl. Bye fuel (gas propane) No change with either fuel . It will start and run fine for about 4 to 5 seconds then it drops a cylinder (miss). You can momenterly trigger the
aux. power switch in the basket, then it picks up the dead cylinder for a split second and the miss is back. The check engine light does come on. When the diagnostic switch is used from the ground controls it flashes one, one two, one two three. I' am told this is the coil pack. New coil pack , engine still has a miss. It has back fired before then the miss will go away for a time then it comes back. I have changed the plugs and ohm'd the plug wires, still have a miss. Thanks for sharing any thoughts. Tim
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  Curtis B. replied 1 year ago.
Compression test? All cylinders close to the same? Is this the dual spark plug engine, with two plugs per cylinder? It starts ok and seems fine for a short period? Has the timing belt ever been replaed?
Customer: replied 1 year ago.
Hi Curtis, All cylinders are within 15 lbs. This engine does have 2 plugs per cylinder with the holes on the exhaust side plugged with factory plugs and still painted black. Timing belt is a gates belt and was changed about 50 hrs. ago. This machine ran fine till last fall. It also has fresh fuel and filters. Tim
Expert:  Curtis B. replied 1 year ago.
??The second plugs have spark plug wires to them? And never been changed?
Customer: replied 1 year ago.
Hi Curtis, The holes on the exhaust port side of the head have been plugged (no spark plugs or wires).
Expert:  Curtis B. replied 1 year ago.
OK. Have you ran a spark test on the unit when it acts up? To see if there is erratic spark on one or more cylinders? Need to isolate if it is one cylinder, or all.???
Customer: replied 1 year ago.
Good morning Curtis, When this all started that was one of the first tests I made. That is when I replaced the OEM coil pack. (Parts changing)HaHa. After the fact I ohm'd old and new coil, found out I wasted money. The one thing that stumps me is why does the engine momentarily run fine when you trigger the aux. power switch from ground operation or from the lift basket (platform) ? The aux. switch is for battery powered hyd. recovery system (to get basket, platform down) in case of engine failure. Now I' am looking for voltage drops in both engine management and boom operations? Last fall I ran a pressure test on the fuel system it had 62 psi at idle under misfire and at high idle. What should fuel pressure be? Can't get accurate vacuum reading on engine because of miss! Thanks Tim
Expert:  Curtis B. replied 1 year ago.
Fuel pressure is fine at 60 psi. With engine running correctly when you toggle a function, I wonder if the engine doesn't have a ground problem? Check or add a ground, using a jumper cable as a test.

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