carpdad

Hi, after some reading in the website, I've come up with following questions.
My truck is 1996 f150 base, 4.9L, 6 cyl, fuel injection, manual. Battery test at Autozone, but I don't think their tester does load test. But according to their tester, battery is good.
I understand that starter/solenoid may be affected by age and heat. But there was one post that started the discussion on fuel delivery problem, which I did not fully understand. Any insight is appreciated.
My starting problem is this. It is not affected by dry or wet weather. It is not affected by summer or winter. The truck starts strong when starting from cold engine. It sputters (I am car newbie, but I think the crank is turning) and refuses to catch when the engine is hot and I try to start.
If I start the engine first and give gas while the engine is sputtering, it will not catch. However, if I press on the gas first then start the engine, it will catch after 2-3 turns. I may have to pump the gas.
My questions are:
1. Is fuel sensor at fault? - that there may be too much fuel going into the combustion chamber?
2. Someone posted that in a fuel injection engine, pressing on the gas pedal with engine off does not deliver gas. With this in mind, my engine catches when I am pressing on the pedal and start the engine. Does this somehow indicate fuel pump or fuel pressure regulator problems? By the way, I have 2 fuel tanks and front tank sending unit does not work most of the time. It sometimes works when the weather is hot. I tried fuel injection cleaner without success (one post said this may unstick the float).
3. I did own tune up, changing spark plugs, plug wires, distributor cap and rotor and fuel filter. Plugs were Motorcraft and wires were Bosch. Can any of this cause hot engine start problem?
Sorry for all the questions, and I know my questions are directionless. I would appreciate some explanation on the parts I mention and how the heat affects them. Someone said that heat can decrease the starter motor function. The Haynes manual does not go into this detail. Thank you.

ymeski56

Do Error code scans. If you hold the accelerator to the floor while starting, injector flow ceases. What is your base timing?

carpdad

Thank you for the reply. Just yesterday I also found 2 more causes for the problem I'm having. In auto repair section of About.com, bad injectors and cold start valves are also listed as parts that may cause start problems with a warm engine. I am going to see if I can do these repairs myself. Will do also on error checks. Thanks.

mrberg89

I had a similar problem with my truck. Truck started just fine when cold, but once warmed up I could not start it back up unless I was pressing the skinny pedal. I replaced the ect sensor and the problem was solved.

ymeski56

Cold start valves? How about something you actually have. There is a test procedure on the link (IAC): http://www.fordfuelinjection.com/?p=39

carpdad

Lol, I really don't know what I am talking about. I google Hot Engine Start Problem, and I get all kinds of answers, and admittedly I am throwing darts blindfolded. What I figure is if I do enough research I will either find the part or will not. Paying the mechanic may be the easier way to go, but I got the bug and want to try at least locating the parts and see what I can get my hands on. I just found out that I may have TFI-IV (DI) system and may have a square type ignition coil!
Problem is that heat seems to do all kinds of things to ignition coil, starter and starter solenoid, at least according to some posters here as well as other websites, but then problem may be bad injectors, air and temperature sensors, fuel pressure regulator, ground, battery cable, etc.
So now my head is spinning.
Added to that is I have excellent start on cold engine and driving/idle is no problem.
I think the error code check is the place to start. Otherwise, I think I am going to start checking what I can or replace what I am sure of, such as starter. Someone mentioned that starters can go bad due to age. I figured that easy-to-replace and relatively cheap parts can be replaced new without feeling wasted that money.
Anyway, thank you for the suggestions and will check the codes and sensors.

mrberg89

My vote is still for the ECT needing replaced. It's a cheap part and only takes about 5 minutes to replace. May as well try it. Your problem sounds identical to the one I was experiencing.

ymeski56

When you google, add F-150 to the search. Error code scans will cough up bad sensors! https://www.f150forum.com/f10/how-re...es-obdi-10907/ or the easy way http://www.handsontools.com/Equus-In...ol_p_5574.html Could be the ECT or TPS or....... Did you clean & test the IAC as mentioned in the link posted previously???

carpdad

Both mrberg89 and ymeski56, thank you for the ideas. Went to Autozone for code reader but somebody had already rented it. Will check for codes as soon as I can get the reader.
I like to try changing the ECT sensor but there is no picture of its location in the whole internet! F150 truck is most popular truck but there isn't much photos of its parts. I know what it looks like from Autozone site and took down some posts about where ECT might be - that is, near the thermostat housing on a metal hose. Now I have to find thermostat.
ymeski56, thanks for the link. You wrote IAC, and the link is for IAB (idle air bypass). Are these the same? Is it also known as idle air control?
Again thanks and will post the result as soon as I get them.

ymeski56

A Vatozone w/ an OBD 1 code reader to loan? That's amazing! Yes, the Incomeing air control valve has at least 9 alias's that I know of. You need to P/U a Haynes manual for your truck. Under hood, center, front engine area, mounted in driver side front of cylinder head. Looks like this: http://www.fordfuelinjection.com/?p=28