difficult starting after short trips

[jsomedaysoon]

I know this has been gone over a few times and ive spent a while looking through old threads but i've still got a few questions. heres the issue though. On my 86 when i make short trips and frequent starts and stops it doesent want to start. it always starts after a few minutes of trying but its getting anoying and its giving broncos a bad name lol. it just looks bad when i'm sittin there in the parkinglot cranking with no results. the starter is only about a year old but we havent driven the truck that much in the last year so its relitivly new. all the plugs, wires, cap, rotor, and filters are new. the TPS senser is new too. Now after looking through other threads one thing that i noticed is a guy said that his headers were cooking his starter and once it cooled down it started. all he did to fix it was to insulate the starter. does that sound logical or should i look more into the ignition aspect of it? It cranks strong when i'm trying it. it just doesent start. I feel like that was kind of complicated so if anybody is confused i will try to clear it up lol.

edit: i didnt change the TPS sensor it was the ICM that I changed. not sure why i was thinking TPS but what ever... just for the record the TPS looks factory.

 

[Seabronc]

If the starter is turning the engine over, then it is not the starter. The overheated starter causes it to either not turn the engine over or not wok at all until it cools down. You need to differentiate between fuel supply when it won't start and spark. Then direct your trouble shooting in the right direction. Otherwise you will be replacing good parts and wasting your money. The thing to do is pull a plug wire and see if you are getting spark from the wire to the engine block. It should be a good strong spark and not a little weak yellow thing. If it seems good then you need to look into the fuel end of it. All you need for ignition is (spark, and a good fuel to air ratio). Since you said you have a TPS I assume you have a 302 EFI engine.

Good luck,

>-

 

[jsomedaysoon]

yea it is fuel injected. i thought that was in my sig but maybe not. the only problem with checking the plug wire thing is it usually happens when i'm alone. maybe i'll take my girlfriend for a ride tonight and just stop at a bunch of places until it wont start anymore then try it.

 

[Seabronc]

yea it is fuel injected. i thought that was in my sig but maybe not. the only problem with checking the plug wire thing is it usually happens when i'm alone. maybe i'll take my girlfriend for a ride tonight and just stop at a bunch of places until it wont start anymore then try it.

You may have had that there, but us OLD guys can't see good :blush:

>-

 

[jsomedaysoon]

haha na i just stuck it in there. i thought i had it in there before but i didnt.

 

[bluesman17]

I had this same issue. Mine turned out to be the fore-shadowing of my fuel pump giving out.

 

[jsomedaysoon]

thanks for the jynx dude! haha na that would be my luck. eh well. i'll get to add that to the list of things i can do!

 

[BroncoJoe19]

In addition to SEaBronc's suggestion, you could try pulling codes, that might point you in the right direction.

All you need is a 4 inch piece of wire and the ability to count to ten /emoticons/[email protected] 2x" width="20" height="20" />

http://broncozone.com/forums/index.php?s=&...ost&p=74581

Another thing to try is, the next time it won't start is to try holding the pedal to the floor and crank it for no more than 15 seconds at a time. IF it starts, then you may have a sticky IAC.

You may have a faulty IAC anyway.

Try to check and clean the Idle Air Control valve IAC

http://www.fordfuelinjection.com/?p=39

Good luck, let us know how you make out.

 

[92bronco_in_progress]

In addition to SEaBronc's suggestion, you could try pulling codes, that might point you in the right direction.
All you need is a 4 inch piece of wire and the ability to count to ten /emoticons/[email protected] 2x" width="20" height="20" />

http://broncozone.com/forums/index.php?s=&...ost&p=74581

Another thing to try is, the next time it won't start is to try holding the pedal to the floor and crank it for no more than 15 seconds at a time. IF it starts, then you may have a sticky IAC.

You may have a faulty IAC anyway.

Try to check and clean the Idle Air Control valve IAC

http://www.fordfuelinjection.com/?p=39

Good luck, let us know how you make out.

good call broncojoe.......i was trying to figure out what it could be but the IAC kinda makes sense.....when it gets warm its shorting or something like that......take it apart and clean her out

 

[jsomedaysoon]

cool thanks. thats something i can do for free and wont hurt even if its not the actual problem. i've got a big day tomorrow but i should be able to do it sunday.

 

[92bronco_in_progress]

cool thanks. thats something i can do for free and wont hurt even if its not the actual problem. i've got a big day tomorrow but i should be able to do it sunday.

if that doesn't do it, try checking your fuel presure just to make sure

 

[jsomedaysoon]

okay i cleaned the throttle body, and tightened the screws on the idle air bypass. (top one was loose) and now i think its running a little worse actually. my idle is a little bit irregular and when i'm driving down the road at a consistant speed with no change in the gas pedal my rpm's will dump off like the motor just stalled and i'll have to rev it up to get some speed back out of the motor. Does anyone have a link to how to test the fuel presure. also should i check the presure when the motor is cold ( it starts fine when its cold) or should i just check it when its giving me problems. Oh and as far as the codes go i only have a digital volt meter. would that work the same way?

 

[92bronco_in_progress]

okay i cleaned the throttle body, and tightened the screws on the idle air bypass. (top one was loose) and now i think its running a little worse actually. my idle is a little bit irregular and when i'm driving down the road at a consistant speed with no change in the gas pedal my rpm's will dump off like the motor just stalled and i'll have to rev it up to get some speed back out of the motor. Does anyone have a link to how to test the fuel presure. also should i check the presure when the motor is cold ( it starts fine when its cold) or should i just check it when its giving me problems. Oh and as far as the codes go i only have a digital volt meter. would that work the same way?

check it when its acting up on you......there is a tool for checking fuel presure its like a oil preasure tester but for fuel

 

[jsomedaysoon]

If the starter is turning the engine over, then it is not the starter. The overheated starter causes it to either not turn the engine over or not wok at all until it cools down. You need to differentiate between fuel supply when it won't start and spark. Then direct your trouble shooting in the right direction. Otherwise you will be replacing good parts and wasting your money. The thing to do is pull a plug wire and see if you are getting spark from the wire to the engine block. It should be a good strong spark and not a little weak yellow thing. If it seems good then you need to look into the fuel end of it. All you need for ignition is (spark, and a good fuel to air ratio). Since you said you have a TPS I assume you have a 302 EFI engine.
Good luck,

>-

okay i pulled a spark plug wire off in the dark and while trying to start it i saw zero spark. So i took the wire of the distributor that comes from the coil and tried to start it and got a significant spark. Does this indicate that the distributor is going out? the cap and rotor are new.

 

[92bronco_in_progress]

okay i pulled a spark plug wire off in the dark and while trying to start it i saw zero spark. So i took the wire of the distributor that comes from the coil and tried to start it and got a significant spark. Does this indicate that the distributor is going out? the cap and rotor are new.

thats an odd one.....take the cap off and look for corrosion or anything like that.....pre-mature wear in-other words.....im not sure what else to tell ya.....i don't think it would be the distributor.....maybe there is a crack in the metal in the rotor or something like that......faulty parts?

 

[jsomedaysoon]

okay i grounded the fuel pump spot on the self test thing and listened closely. i heard a two live fuel pumps and a clicking from the fuel relay. All good news right? I'm thinking i'm leaning more towards a spark issue at this point.

 

[92bronco_in_progress]

okay i grounded the fuel pump spot on the self test thing and listened closely. i heard a two live fuel pumps and a clicking from the fuel relay. All good news right? I'm thinking i'm leaning more towards a spark issue at this point.

i would go that way at this point in time too......inspect your rotor and cap, make sure you don't have any cracks or pre-mature wear.....i think you may have a problem when the rotor gets hot.....you may have faulty parts

 

[BroncoJoe19]

Oh and as far as the codes go i only have a digital volt meter. would that work the same way?

You could try it, A digital one is supossed to work, I have never tried it.

Regarding the no spark, I think that in order for the coil to get spark, the rotor has to be turning inside the distributor., But humor my ignorance, and just make sure. Please pull the cap and have someone crank the engine while you make sure that the rotor is turning.

IF it is, put the cap back on, and check for spark from the coil again, and then at EACH of the plugs. You may have a bad set of wires, or your plugs may be too widely gapped. OR as mentioned above, bad cap and rotor.

 

[jsomedaysoon]

Oh and as far as the codes go i only have a digital volt meter. would that work the same way? You could try it, A digital one is supossed to work, I have never tried it.

Regarding the no spark, I think that in order for the coil to get spark, the rotor has to be turning inside the distributor., But humor my ignorance, and just make sure. Please pull the cap and have someone crank the engine while you make sure that the rotor is turning.

IF it is, put the cap back on, and check for spark from the coil again, and then at EACH of the plugs. You may have a bad set of wires, or your plugs may be too widely gapped. OR as mentioned above, bad cap and rotor.

Okay i'll take the cap off and look at that as soon as someone gets home to help. The plugs, wires, distributor cap and rotor are all less than 6 months old. It seems like if the plugs were gapped too widely that it would effect the engine while i'm driving. It runs pretty nice once i've gotten it started.