1995 5S-FE Hard Start

[TRD95]

So my 95 Camry 5s-fe has begun to act up a little bit when it's at operating temperature. I turn it off and run inside a store or restaurant for 15-30 minutes and come back it becomes pretty difficult to start.

I'm sure it's a fuel-related issue but I'm not exactly sure where to start. I'm inclined to place blame on the fuel pump since this would mean it would do it regardless of temperature. I've heard this can be the cause of a bad fuel pressure regulator and/or a bad fuel filter. Fuel Filter was replaced 10,000 miles ago. I'll probably be switching it out later today. Any other thoughts guys?

[Mister_Perkins]

Originally Posted by TRD95

So my 95 Camry 5s-fe has begun to act up a little bit when it's at operating temperature. I turn it off and run inside a store or restaurant for 15-30 minutes and come back it becomes pretty difficult to start.

I'm sure it's a fuel-related issue but I'm not exactly sure where to start. I'm inclined to place blame on the fuel pump since this would mean it would do it regardless of temperature. I've heard this can be the cause of a bad fuel pressure regulator and/or a bad fuel filter. Fuel Filter was replaced 10,000 miles ago. I'll probably be switching it out later today. Any other thoughts guys?

Sounds like you have a good idea of what it might be. If I were you I would get a fuel pressure gauge (you can rent them from autozone and advanced auto). And turn the key to the "ON" position and see what the pressure is. Dont turn start the car. Check the initial pressure, and Wait for like 10 minutes and come back and see what the pressure is. If it dropped you have a seal problem (Pressure regulator) and the fuel is pushing back through the system causing your car to have trouble starting

[Mike Gerber]

Also check the engine coolant temperature sensor for being out of range and also check the coil inside the distributor.

The engine coolant temperature sensor could be out of range and is telling the ECU the engine is cold, when it is actually warm/hot. This would produce a mixture that is too rich for a warm engine, essentially flooding a warm engine.

The coil could also be out of range or have a crack in it. This is a common problem that surfaces as the engine get's warm on cars with a lot of miles on them. Your signature shows 333,000 miles (congrats on that by the way) on the engine. That certainly qualifies as lot's of mileage.

Mike

[TRD95]

Originally Posted by Mister_Perkins

Sounds like you have a good idea of what it might be. If I were you I would get a fuel pressure gauge (you can rent them from autozone and advanced auto). And turn the key to the "ON" position and see what the pressure is. Dont turn start the car. Check the initial pressure, and Wait for like 10 minutes and come back and see what the pressure is. If it dropped you have a seal problem (Pressure regulator) and the fuel is pushing back through the system causing your car to have trouble starting

Originally Posted by Mike Gerber

Also check the engine coolant temperature sensor for being out of range and also check the coil inside the distributor.

The engine coolant temperature sensor could be out of range and is telling the ECU the engine is cold, when it is actually warm/hot. This would produce a mixture that is too rich for a warm engine, essentially flooding a warm engine.

The coil could also be out of range or have a crack in it. This is a common problem that surfaces as the engine get's warm on cars with a lot of miles on them. Your signature shows 333,000 miles (congrats on that by the way) on the engine. That certainly qualifies as lot's of mileage.

Mike

Thank you so much for the replies guys! I'll be in the shop with it sometime this week to figure it out. I have to run the car around for a great while to replicate the problem (about 30 miles on the highway) so I'll be doing a long trip before taking her to the garage. Your input has given me more areas to check out.

For Mike Gerber have you seen the engine coolant temp senor give this kind of issue on other 5S-FE engines by any chance? I can see your argument in this case and I wont rule it out. Just wanted to know if you were speaking from experience. And yes, 333,000 miles is a great milestone for this car. She's been through hell but I haven't left her side. She's been so good to me throughout the years, so I have to treat her with respect

Mister Perkins I have to hand it to you, you're giving a lot of your time to the Gen 3/3.5 community. I've seen your new website and I'm very impressed. Thank you so much for your contributions. If there is anything I can do to help please don't hesitate to ask me. And also thank you for your suggestions, I will be pressure testing the system as soon as I get some free time. By the way, is there any chance the Idle control valve or any throttle related component be causing this condition?

Any other suggestions are welcome!

[Mister_Perkins]

TRD, I really appreciate that. I'm glad that you find my information useful / helpful

The IACV you would most likely see the car start right up and die real quickly, or start up (when cold) And Idle really really low.

Since it happens once the car heats up it could be a lot of things. When things heat up, they expand. So you may have a contact issue with something electrical that once that car heats up it may loose contact when turned off. If your fuel pressure and the Coolant sensor check out, I would look into checking the ignition system for proper amount of air gap on the distributor and the proper amount of resistance on the coil and igniter.

Just a thought

[Bdub215]

Heatsoak from your intake. If IAT's get high enough, timing gets pulled, car drives like shit and its hard to start.

[TRD95]

Originally Posted by Mister_Perkins

TRD, I really appreciate that. I'm glad that you find my information useful / helpful

The IACV you would most likely see the car start right up and die real quickly, or start up (when cold) And Idle really really low.

Since it happens once the car heats up it could be a lot of things. When things heat up, they expand. So you may have a contact issue with something electrical that once that car heats up it may loose contact when turned off. If your fuel pressure and the Coolant sensor check out, I would look into checking the ignition system for proper amount of air gap on the distributor and the proper amount of resistance on the coil and igniter.

Just a thought

Originally Posted by Bdub215

Heatsoak from your intake. If IAT's get high enough, timing gets pulled, car drives like shit and its hard to start.

These are all valid arguments. Will check them all out and post any updates. Thanks guys!

[Stillrunning]

Originally Posted by TRD95

I turn it off and run inside a store or restaurant for 15-30 minutes and come back it becomes pretty difficult to start.

I assume the engine cranks normally but won't start?

There is nothing wrong with a fuel filter with 10k on it. If there were you'd get engine operation problems at high rpm/high load. If you get a fuel pressure tester make sure it has a banjo bolt adapter for the Camry. If fuel is leaking back through the system then it would be worse when left overnight and your cold start would be also hard. Mike Gerber's pretty sharp but I think if the ECT sensor is out of range you would get poor idling and even poor operation at speed, you'd also get very bad fuel mileage of course. It could be leaking injectors that drip raw fuel into the intake and give you a rich mixture. Overnight the fuel would evaporate and so not show up when engine is cold, as well a rich mixture when cold is usually not a problem. Poor spark when hot can be checked by checking the spark, you can also see if the plugs are wet with fuel. I'd think if it were the coil putting out poor spark when hot then you'd also get poor operation under speed.

[Mike Gerber]

"For Mike Gerber have you seen the engine coolant temp senor give this kind of issue on other 5S-FE engines by any chance? I can see your argument in this case and I wont rule it out. Just wanted to know if you were speaking from experience."

Yes, I'm speaking from lot's of years of experience in backyard wrenching, lot's of time on this forum and also following a logical path to what could be causing problems when the car heat's up. Mister Perkins gave you 1 of the 3 common problems that could cause this, I simply added the other 2 common ones. I probably should have listed the coil first, since that is a bit more common than the engine coolant temperature sensor. Still running's point about leaking fuel injectors could also cause the problem you are experiencing, but that occurrs less often then the other 3 things, IMHO. The pintle (the tiny opening on the end of the injector) that Toyota uses is fairly large and doesn't clog too often.

Let us know what you find.

Mike

[GTcelica22]

i'm interested in knowing what the solution was to this, as i am having the same problem.