Aluminum Block V8s 4.1, 4.5, 4.6, and 4.9 liter engines.

help needed

Old Mar 13, 2010 | 06:37 PM
  #1  
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Angry help needed

just got motor back together after both head gaskets replaced (99 sts y code). new used maf, new batt, fresh gas, but have maf code and an evap code comming up. wont idle, runs rough (very) if i get it to start. i can hold the gas ped. down and get her to start, but she doesnt like it.
 
Old Mar 14, 2010 | 12:15 PM
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Specific codes would help.
Sounds like you have a vacuum leak, or possibly plug wires crossed. A rough idle from bad plugs/wires/ign module/injectors will set seemingly unrelated codes.
Have you tried to re-install the "old" MAF sensor?
Are you absolutely certain the cams are all timed properly?
 
Old Mar 15, 2010 | 07:29 AM
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forgot the codes at the house, p01010 i believe is he maf sensor. there is a p1645 also. i think this was th evep code. cams were timed right. used chiltons manual from local library. the guy who took it apart was not able to put back together. another guy put back toether. both ase cert, but its never fun cleaning up someone else's job
 
Old Mar 15, 2010 | 12:42 PM
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P1645 = Evap Purge Solenoid Output circuit
This means the PCM did NOT see the line go to ground when it was commanded, or it sees the line is grounded when it should be off. Could be a loose connection, or a grounded wire in the harness...or a bad solenoid.

No such thing as the P01010, so I'll assume it is actually a P0101, which is a "Map Sensor Performance" code. The ECM monitors the MAP frequency to determine if it is stuck low, high, or otherwise not providing the airflow value it expects to see for a given condition, or is not providing the signal variation expected. MAP sensor testing is fairly involved, and requires a bit of time, and test equipment(a multimeter with frequency capabilities is nice). A wiring diagram will also be needed. If you do not have the FSM(Factory Service Manual), it's gonna be tough to troubleshoot this.
I believe this code is going to be from a vacuum leak, or an engine miss issue. btdt.
hth
 
Old Mar 15, 2010 | 06:50 PM
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Check grounds at engine and transaxle also...loose ground wires "happen" alot when cars are taken apart by one person and re-assembled by another.
 
Old Mar 20, 2010 | 03:29 PM
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great news!!! i need to know where the best place to get a reman. front head would be? any ideas! no comp 1n cyl 2, 60 in 4, 0 in 6, and 100 in 8. o reilys has em 700 buks ready 2 go..........................

we had it timed wrong and toasted the valves i bet. dont have it tore
bak down yet, but is ther a cheaper way to go?
 
Old Mar 20, 2010 | 05:18 PM
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I suggest to reset timing chain and see what happens, piston do have valve reliefs, there is a chance valves are not bent. If your lucky you won't need a new head. 2000 and later don't have valve reliefs in the pistons.
 
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