1994 Camry XLE 4cyl

[qwerty4321]

Hey everyone, from los angeles. my brothers Toyota Camry XLE 4 cyl. is difficult to start up. He has to give gas for it to idle at a higher rpm so it would have more power. My uncle (lives in s.f) is a mechanic and said that something "valve" is messed up or clogged, does anyone know how I can fix this problem myself?

- So right now, it's runs on 3 cyls if we don't give gas for it to warm up the 4th valve.

I just think that giving more gas is a big problem due to the expensive gas prices these days

[Brian R.]

Clean your IAC valve.

[vicchang]

Originally Posted by qwerty4321

Hey everyone, from los angeles. my brothers Toyota Camry XLE 4 cyl. is difficult to start up. He has to give gas for it to idle at a higher rpm so it would have more power. My uncle (lives in s.f) is a mechanic and said that something "valve" is messed up or clogged, does anyone know how I can fix this problem myself?

- So right now, it's runs on 3 cyls if we don't give gas for it to warm up the 4th valve.

I just think that giving more gas is a big problem due to the expensive gas prices these days

Difficult to start and difficult to keep it running at idle are 2 different problems.

1. Your cold injection valve or related parts could be faulty so it's hard to start.

2. If it's on 3 cylinder, the car should shake badly on idle. You can test if a cylinder work by pulling out the plug wire one by one to de-activate that cylinder. The engine should stall or run worse. If the engine sounds the same, then that cylinder is not working. Then you can start from there -- find out what's wrong with that cylinder. You can take off the plug to see if it reveals any info, you can do compression test, etc.

3. If the engine problem is caused by carbon deposit on the piston/valves, you can try Sea Foam to burn it up.

4. Check the EGR valve, to make sure all the passages are clean and not clogged by carbon deposit. You can only manually clean up the deposit if any.

[Brian R.]

"1. Your cold injection valve or related parts could be faulty so it's hard to start"

Although some engines have cold-start injectors, your engine doesn't - so that's not possible.

[qwerty4321]

I have no idea how to "Clean the IAC valve"

" the car should shake badly on idle" It doesn't shake, because when starting the car up, we usually give it gas so the 4th cylinder would work.

[Brian R.]

Remove the valve, and clean it by hand. It's located on the underside of the throttle body, and is held on by four phillips screws. Use good quality cleaner that's sensor safe.

[vicchang]

Originally Posted by qwerty4321

I have no idea how to "Clean the IAC valve"

" the car should shake badly on idle" It doesn't shake, because when starting the car up, we usually give it gas so the 4th cylinder would work.

Ok, that's my question, how do you know your car is running on 3 cylinders? It's unlikely that one cylinder doesn't work at start up but works fine after.

I would suspect your EGR valve. Take it off and clean up the carbon deposit and make sure the valve moves freely. If the EGR stuck open, it's like leaking in the intake, so the engine will be difficult to start and the idle will be rough.

[Daniel M. Dreifus]

Here's my take on this - also 1994 4 cylinder Camry.
Your car feels like it is running on three cylinders at cold start up because the IAC (idle air control valve) is sticking and not enough fuel gets into the cylinders for smooth cold start up idle speed.
If you remove the hose clamp at the throttle body opening and pull aside the large black air intake hose - at the bottom of the throttle body is a small rectangular hole - the air inlet for the IAC valve.
The best cure I've found for a sticking valve is TriFlow. It is a lubricant with teflon sold at bicycle and hardward stores.
Just spray a small amount into the IAC air intake with the engine cold and stumbling at idle.
After I removed the throttle body, replaced the IAC valve with new, and performed all the adjustments and calibrations for the TB according to the factory service manual, this annoying sympton of cold start stumble returned but the TriFlow seems to have cured it.
My best guess is that the cylinder disk that covers and reveals the air port inside the IAC valve has no lubrication and the bimetallic thermostatic coil on the other end of the shaft running through the valve sometimes doesn't develop enough pressure to fully open the valve when cold.

[AccordCodger]

Another point to remember is that ANY 4 cyl car that is only firing on 3 cylinders will smoothen out at higher revs. That does NOT mean that the 4th cylinder is then working. And you will damage your motor if you drive far on 3 cylinders.

[Brian R.]

Good post Daniel - I added your discussion to the FAQ under the IAC-cleaning issue.

[Toysrme]

Werd with the IAC. Just pull it off & clean it.

We're all acting like this is a really complicated problem to answer LoL!

Cleaning the IAC will solve it & then we can troubleshoot anything else that's left. If it doesn't get a single bit better, it's preventative maint & should be done every few years to start with. We can't troubleshoot effectively until it's done anyway. Which brings us back to...


We are making this way too complicated LoL!

Take the IAC valve off & clean it, & get back with us on how it turned out / any other problems.

[Brian R.]

We're just not happy unless there is a complication to deal with...

[qwerty4321]

thanks everyone... I've been busy lately, i'll let my brother read this so he would try to repair it hiimself, i'll post back with results

[qwerty4321]

Ok... I attempted to take it out but I wasn't able to take out the other 2 screws, somehow someone... or I destroyed it =\ how would i take it out?

[qwerty4321]

i just want to say thanks for everyones advice, and all i did was clean out the IAC, there was lots of carbon deposits.