97 tacoma hard to start on warm days at running temp

i have been reading threads and taking all suggestions and nothing has prevailed to be the all mighty fix! i have replaced throttle body sensor, MAF sensor, crank shaft sensor, 1 of 3 coil packs, new wires...at my wits end.

Its not throwing any codes!!

HELP!!!!

 

Lots of things can cause this. A scan tool that can give you live data, and a fuel pressure gauge would be a great help to you. Have you done all of the regular maintenance, including replacing the fuel filter? I noticed you mentioned new wires. How about plugs?

 

replaced wires, plugs, fuel filter, fuel pump @1 yr ago, thermostat...

 

Throttle body sensor? You mean TPS? That shouldn't have much to do with your issue.

I'd check the coolant temp sensor.

 

coolant temp sensor? would this is a possibility even if the truck isnt overheating?

I've read on a forum this morning about the air flow sensor...located inside the air filter casing....your thoughts?

also...whats your thoughts on a heat soaking issue with the starter...something simple being its not throwing a code, but hidden enough to be a pain in my butt! if this would be the case, what are the possible heat sources? i dont hear an exhaust leak...i read somewhere they recommended a heat wrap for the starter?

 

The IAT (intake air temp sensor) could be going bad, too.
The CTS tells the computer whether or not the truck is cold or hot, and that would cause bad warm starting while cold starting is just fine.

You need to check the FSM and start checking those sensors.
Guessing isn't going to do much.

 

agreed..guessing is running me broke and leaving me frustrated.

 

OK, hang on a second. Let's make sure we are looking at the correct problem. There is a difference between a engine not CRANKING, and an engine not STARTING. Your question about hot soaking causing an issue with the starter has prompted this question.

Does the engine turn over normally, but won't start after a hot soak, or does it not crank at all?

A bit vague on the understanding of your complaint at this point. Cranks won't start, or won't crank at all?

 

starter turns..but engine wont fire up. well correction, it will start...eventually, but then backfires, almost like its flooded.

 

..and yes, when its cold, it fires right up, without hesitation. in the winter it will start right up, even when at running temp.

but when its warm and at running temp, it'll acts like its flooded when starting

 

OK, thank you. I was just wanting to be sure. A hot soaked batter would not be the issue then if it still turns over at normal speed. So you can eliminate that as an issue.

A malfunctioning coolant temp sensor COULD cause an issue like this, but I am not 100% sure this is your fault. I will have to look some things up.

I would be a LITTLE suspicious of a bad fuel pump. Have you noticed this ocuring all the time, or perhaps only when you are at 1/4 tank or less, on a hot/warm day?

 

I would greatly appreciate you taking time to research this issue and attempt to help me!!!!

 

fuel level doesnt affect it. yesterday, after i replaced the crank sensor, i had 3/4 of a tank and after i got it to running temp, turned it off, let it sit for 15 min, i had the same issue

 

I hate to say it, but at this point I think your money would best be served by getting someone with a scan tool to take a look at it. Any of a number of sensors could be failing after getting hot, the fuel pump could be failing after getting hot (Even though the fuel pump is in the tank, it is not uncommon for them to get hot, and fail), the ECM could be getting hot (Though I doubt it is the cause, it is not unheard of) my diagnostic information shows too many for making a guess. You really need a professional to look at it. I would be happy to, but I don't think you want to take a road trip to Alabama. lol.

 

although a trip to Bama would be awesome, i dont think that is feasible at this point lol but i do thank you for your input and greatly appreciate your time and efforts in helping me. I will definitely post the fix..whenever I locate it!!

 

Well don't abandon all hope with us yet! Once you get more information we may be able to help you with finding a low-cost fix or alternatives. Let us know what you find out!

 

oh i NEVER give up hope...once hope is gone, all is lost!! lol

i will definitely post anything i discover during this process --- on the plus side, i'm learning a ton about yota's, nothin wrong with that!!! lol

Thanks again for all your help, truly appreciate it!!!