Hot start problem

[stonie13]

I have an intermitent problem that occationally occurs after I drive for a while. Stop, turn off the Explorer. 5-10 minutes later the truck wont start. Cools for an hour & it starts & runs full power. No problems. What could it be. I was thinking fuel pump but I tried starting fluid while having the issue & still no start. There is pressure at the injectors. No codes. Everything works fine. My next step is the ECT sensor. Any other suggestions.

 

[2000StreetRod]

ECT sensor

I agree that your symptoms are typical for a defective engine coolant temperature sensor. If the PCM thinks the engine is cold due to a defective ECT sensor then it will richen the fuel mixture for a cold start. Since the engine is actually warm the excessively rich mixture prevents the engine from starting. Spraying starting fluid into the intake tube would further richen the mixture.

Other possibilities are sticking IAC valve (try cleaning it), a dirty MAF sensor (causes rich mixture at idle and lean mixture at moderate rpm) and stuck open fuel injector (try adding fuel injector cleaner). Some cheap fuel injector cleaners cause deposits to collect on the intake valves inhibiting warm starts. I only use Techron fuel injector cleaner for that reason.

 

[stonie13]

I am going to replace the ECT & clean out the IAC & MAF this weekend. Did it agian yesterday. Went back 45 min later & worked perfectly. I have been using Lucas Injector cleaner on fill ups once a month. Thanks for the info I will post what I find out.

 

[stonie13]

Havn't had time to do any repairs yet but since the weather got nicer & the temps are higher my Explorer has stalled twice while driving & won't start for a while. Am I still on the right track?

 

[Allmost 50]

Stonie13, How many miles are on the spark plugs? Fouled plugs (weak spark) will run fair, but they will make an engine hard to get going when hot.

 

[stonie13]

Not sure. Bought it last June & haven't had time. It's on the list. It runs great w/o hesitation on miss. The start problem is intermittant so I ruled that out.

 

[jmu4032]

i have the same problem, i was towed to a ford dealer, they ran all kinds of tests with no sure results. the big fix was replace the fuel pump @ $1100.00. i'm still hunt for a solution.

 

[stonie13]

I decided to try the cheap stuff first & I replaced the Coolant Temp Sensor. Cost $16 & tool about 45 minute. Been good ever since. Did it about a month ago. Good luck.

 

[Jauto]

Stonie13 have you found the source to the problem!? I am having the exact same issues

 

[BKennedy]

This thread is 10 years old and the last post before yours was Stonie13's last post on the forum. I don't think he will be back to answer your question any more than he already did with saying he replaced the coolant temp sensor.