New engine barely runs...

JonezySN95

JonezySN95

Member
May 18, 2011
206
3
19
J-ville NC
#1
I just put a fresh rebuilt motor (details in sig) and im having major issues with it. It barely starts, wont idle at all, burns your eyes when it does run, and backfires sometimes. I have changed the dizzy, cap, rotor, plugs, and wires. still no luck. It sounds like the timing is off but im absolulty positive its correct at 12*. just to be safe the HB hasnt spun I have a new one on the way. I pulled codes and it flashed 327, 113, and 122. 327 is egr sensor but thats no biggie cause i pulled all that out. 113 is the IAT sensor and 122 is the TPS. My question is... would those 2 going bad make the symptoms that I am having or does it sound like something else in the mix along with those bad sensors? Im super frustrated with it at this point and my brain is fried going over everything from timing chain to coil to all electrical connections. Also the engine i pulled out ran perfectly fine when I yanked it so how is it now that multiple sensors go out at the same time without even being handled? Any help and input is greatly appreciated!
 

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#2
well the tps is going to tell the motor how much to dump the fuel. if you are more than 1 volt with the throttle body closed then you are out of range (.5 to 1 volt is the spec) and the motor is taking it too much fuel and more than likely fouling the plugs already depending on the time it has been running like that. as for the iat, its doing the same for fuel delivery as well but for the air/fuel curve. do you have a multimeter so you can check the values? as for the backfiring, are you sure you are at 12 with the timing spout out? not trying to doubt you but some people have other people do the work and take their word on what was done.
 
#3
i just saw in your sig that you have a v6 with the 5.0 swap. did you swap out the computer and harness as well? and also do you have the right plug wire orientation for h.o. which is 1-3-7-2-6-5-4-8? cant remember the non h.o. routing. that would also make the car run like crap.
 
#4
Yep did it with the spout out. Yeah its the H.O. firing order not the standard 302 wich is 1-5-4-2-6-3-7-8 (though I did try that one just to be safe). Im not sure about the wiring harness and comp cause I got the car with the swap already, but like I said it ran perfectly fine with the stock 5.0 in it. As far as the multimeter yes I have one... do you know of anyother tests and how exactly to do them? I can run and do the tests tomorrow. Oh yea and my plugs did just foul out and I just replaced them but I dont want to keep doing that because with the gt40p heads you have to take the drivers side header off just to get number 7 plug out... a real pain in the arse :nonono:
 
#5
FWIW the Haynes manual doesn't have the correct TPS voltage range. The range is between .66v - 1.2v. (as per the FORD electronic service manuals) Within this range the PCM will learn the voltage setting for the idle position.
 
#6
Ok thanks Toyman. I'll check it out tomorrow and let you know the results. Hopefully after countless hours of testing, buying, and changing parts I've found my culprit. It still baffles me though wondering how both of these sensors went out at the same time when they works fine days before. Oh well let me just pray this works...
 
#11
Well I figured it would be easier to just buy the new sensors since they werent that much anyways. I have been driving around all day looking for a place that had the TPS. I finally found it at NAPA but heres the problem... The part I have has F2SF-CA on it and the one out of the two options that they had is the F1SF-AA. The manager said it would work but I dont trust part sellers. No where else has either one and cant get them at all either. Is there a huge differance in these parts and will it even work? I went ahead and bought it just to be safe but if it wont work then I will just take it back. If you have any experiance with this TPS issue then please help. Thanks
 
#12
Ok well the new TPS was at 1.036v and also put the new IAT sensor on and no change in the way it runs (if you call that "running"). When I ran the codes I noticed something interesting though. The check engine light is supposed to flash 11 to show the ECU is running correct right? It goes through the tests where you can hear the fan kick on 2 diff speeds and a couple little clicks and the light kinda flashes 11 but its more like a weak flicker 11. Does this mean my ECU is time to get replaced and tuned? I may just switch to carb since I have an intake just need to pick up a carb. If I do this temporarly then what do I have to do to keep my check engine light off? That is assuming the EFI system is my problem :shrug:
 
#13
JonezySN95 said:
Ok well the new TPS was at 1.036v and also put the new IAT sensor on and no change in the way it runs (if you call that "running"). When I ran the codes I noticed something interesting though. The check engine light is supposed to flash 11 to show the ECU is running correct right? It goes through the tests where you can hear the fan kick on 2 diff speeds and a couple little clicks and the light kinda flashes 11 but its more like a weak flicker 11. Does this mean my ECU is time to get replaced and tuned? I may just switch to carb since I have an intake just need to pick up a carb. If I do this temporarly then what do I have to do to keep my check engine light off? That is assuming the EFI system is my problem :shrug:
Click to expand...

The codes are all 3 digits. FWIW 111 is a pass code. Switching to a carb setup isn't as easy as you are thinking.The ECU is not likely to be the source of the problem. For $30 you can buy an OBD1 reader.

Save on Equus 3145 at ToolTopia.com
 
#14
toyman said:
The codes are all 3 digits. FWIW 111 is a pass code. Switching to a carb setup isn't as easy as you are thinking.The ECU is not likely to be the source of the problem. For $30 you can buy an OBD1 reader.

Save on Equus 3145 at ToolTopia.com
Click to expand...

I know a carb setup isnt easy. I have done this swap once before with a friend I just never got to all the electrical stuff since I left for the military before he finished. It doesnt flash 111 for some reason, it just kinda half*** flashes 11 but looks like it has a short in the wire while doing so. Then after the 11 it flashes the other 3 digit codes nice and clear. Do you think that it may need a tune at least since it has a bigger cam, heads, intake, and bore to run/idle right? I really dont want to do a carb swap to find out its something non-electrical. I have done a compression test and it came back good so I know the valves are seating properly. I have 3 other options in mind if its not electical... 1) the throttle body is out of wack with this new setup. I've messed with it a little bit but it didnt make a differance and I was in fear I would create more problems so I left it alone. 2) the timing is still out somehow which is why I have a new HB on the way to eliminate this option for good. Or 3) It has some sort of custom cam that needs a specail timing setup ie. firing order, timing point ect.ect. I am still trying to get ahold of the builder to find out the details but I cant imagen it is anything really crazy or off the normal track of the ordinary for a 5.0. I have adjusted the timing back and forth several times even to include jumping over a tooth left and right just incase my stock HB has spun but the best I can get it is to where it barely even starts with no idle. Any other adjusting and it wont even start at all. And just to show that I know about the task in front of me to switch to carb here is a link that gives the headache in detail.

EFI to Carb conversion..... - Ford Mustang Forums
 
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