1997 Camry won't start

My 1997 Camry won’t start off and on. It seems to do it after I’ve run several errands, i.e., started and stopped the car several times, and it seems to happen when the weather warms up (from the 20’s, 30’s to 60 degrees or so)

All the regular things have been checked (battery, alternator, starter.) I have a mechanic who specializes in imports and has lots of experience with Camrys. He thought it was the idler but replacing that didn’t help. He tried putting in a computer but that didn’t solve it. He doesn’t think it’s the gas pump because he used something to test that and it showed it was getting gas fine.

We tried the theory of “winter gas,” but that doesn’t seem to be it either. I was buying gas at Walmart so I switched to Chevron but that didn’t help.

We are at a loss. Does anyone have any ideas?

This is very difficult to troubleshoot unless the mechanic actually witnesses the no start condition and can perform some basic troubleshooting when it isn’t starting. I’m guessing that it works just fine when it is at the mechanics.

You need three basic things, fuel/air ratio, spark and compression. I think you can rule out compression as the engine runs sometimes, so it is either fuel or spark. Even though your mechanic tested the fuel pressure, if the fuel pump relay were failing intermittently, you could have an occasional no start due to fuel. This is not a common problem with Toyota’s though, much more common on Honda’s.

If it is a spark issue, then the cam position sensor or crankshaft position sensor would be the most likely suspect.

My mechanic thinks it might have done it once for him but he’s not sure (for a reason I can’t remember). Because it only seems to do it when it’s warm outside, it has been especially difficult to get it to do it (of course when I’m driving it, it’s warm and it does it.)

He said the fuel is reading a little low for what it should be at but that reading didn’t change when it did its thing.

Does that ring any bells for you?

What exactly happens? Does the engine turn over, but not start? Or does nothing happen when you turn the key?

I agree with Keith. Sounds like it could be a crank or cam position sensor due to it failing when its warm.

If the guy is on your routes, stop by his place every chance possible, if it exhibits the no start condition hopefully a mechanic will be able to diagnose it in failure mode. How do you get it started afterwards? Call AAA, they come out, turn the key and it starts?

My first guess – providing the engine cranks ok – would be a cam or crank sensor on the fritz. I wouldn’t just go replacing them though, until confirming that component is what is actually causing the problem.

When I turn the key, it turns over and makes noises like it’s trying very hard but doesn’t quite start. I try two or three times to start it (and hitting the gas pedal very hard at the same time) but nothing happens. Then I find someone to give me a jump start and it starts right up. My mechanic thinks the jump start is coincidental though.

This last time I let it sit for awhile and hit the gas really hard and it went.

It is definitely related to warm weather. When it’s in the 30s or 40s it won’t do it. When it gets up to 50s or 60s it does it. I can usually make one or two stops and it’s fine but then on the third or fourth stop it won’t go. Although on one especially warm day it did it after the first stop.

So there’s no point in trying a gas pump? My mechanic says it’s every expensive and then may not be the problem.

Am I doomed to living this way until it’s warm and he can see it in failure mode?

Tell you mechanic to check the residual fuel pressure when the car is hot - that is, tell him to look at what happens to fuel pressure on a hit shutdown. If your fuel pump does not hold pressure and it gets nice and hot under the hood, the fuel in the rail can vaporize and cause all kinds of havoc on a restart. The other thing this may indicate is fuel injectors leaking and flooding the cylinders - that may be why flooring the pedal helps.

It sounds like you said that he found your fuel pressure a little low. If that’s the case then you should just replace the fuel pump either way. (Though start with the filter & check again). Fuel injected cars are not happy with pressure outside of specs.

Anything electrical is also subject to problems due to “heat soak” - you shut off the car and it gets hot under there. This can affect any of the ignition related things or things like crank sensors. A little clever investigative work with a heat gun might do wonders.

Winnie … did your mechanic read out the ECM’s active and pending diagnostic trouble codes? I assume they did as you mention the ECM was replaced as part of this.

My guess would be the starter assembly, specifically the contacts in the bendix assembly, and it may be heat sensitive. This is a common problem in older Camrys. And the only way to check for it is to remove the starter, do some disassembly, and check the contacts for carbon deposits and erosion. There is no test that can check for it, and it will not store a fault code in the ECU.

Old starter windings becoming heat sensitive as they age is also common. The varnish-like insulating coating on the winding wires can crack and the windings short with long-term expansion and contraction of the assembly. The copper sire and the polyimide-amide coating expand and contract at different rates, and this can cause fractures that develop in the coating to open when the wire expands and short out. As with the contacts, this can be difficult to diagnose. Sometimes a heat gun can verify it, sometimes it needs soaking at elevated temperatures.

IMHO you’re describing a heat sensitivity issue.

I’m bothered by the fact that your mechanic changed the ECU as one of his first efforts without verifying first that it was bad. This is a very expensive way to do “shotgun” troubleshooting, and it doesn’t give me a sense of confidence. Even for “shotgun” troubleshooting, the ECU should be a last resort.

He found that the idler was sticking and not opening. That’s why he replaced it.

I think that we still need better info about the no-starts. If the car does crank over just fine during these episodes (RR.RR.RR.RR.RR…) then the jump start is coincidental and you’re looking at a fuel or spark problem. But if it only cranks over weakly and getting weaker/slower (RR.Rr.r r…rrrrrrr…rrrrrr… - sorry, it’s the best I’ve got for description) then you’d be looking at power issues including perhaps starter problems.

A strong crank without a start is a very different kind of problem from a weak crank without a start.

Edit: the jump start would be only “partly” coincidental. It makes you open the hood - which helps cool everything off. So whatever is being bothered by the heat may be coming back to normal function.

Winnie … By “idler” are you referring to the engine’s idle air control (IAC) valve? Do you have a list of the computer’s DTC’s yet? Once you post those DTC’s, the experts here will be better able to help you resolve what is wrong.

Cigroller, I’m not sure which description it fits as far as the noises it makes. I’ll try to note that next time it happens (which should be this weekend. The forecast is in the 70’s).

George, I think it’s the engine idler AC valve. Is there another kind of idler? (It’s very hard to remember the terminology he uses because I’m not familiar with it.)

On the DTCs, do you need those readings when it’s actually happening? The weather has been too cold and it won’t happen when he has it.

Because it’s been too cold, yesterday he just put in a crank sensor. (he hasn’t charged me yet because we’re not sure that’s it.)

The Idle Air Control (IAC) valve would make sense.
The details of exactly what he found and did should be on your copy of the shop order. Copying those exactly might help us to better understand exactly what he has found and done.

I’m getting the sinking feeling that he’s not doing good diagnosis, but is instead changing various parts that, while logical, are at your expense. As good a guy as he is, you may need a shop that does diagnosis.

He hasn’t charged me yet. My understanding is he can’t correctly diagnose it unless it’s in failure mode. I’ll find the shop order and post what it says.

BTW it’s not the crank sensor. It failed today when I was out running errands.

The DTC’s can be read anytime. When something unusual happens, the car’s computer will store a DTC in its memory. It isn’t necessary the car be in failure mode to read out the stored codes.

GeorgeSanJose,
Thank you for the info on the DTCs. I will email him and ask him.

GeorgeSanJose, are u talking about DTC codes where the check engine light comes on? When this happens, the check engine light does not come on.