My 1991 Camry wagon has become sick. The first time the problem happened the car started immediately, as always, and as I was backing out of my driveway the engine cut out. I was then unable to restart it. Since then the car has been sitting, and I've had a few attempts to start it. The starter turns the engine over in healthy way, it fires, runs for a second or two, then dies. After this it doesn't want to fire again, but if I leave it for a few days I can repeat this sequence. The petrol gauge shows plenty of gas.
What might be the cause of this problem? Is this the kind of thing that a mobile diagnostic service might be able to diagnose?
The problem is not likely to be a bad fuel pump or fuel pressure regulator because the problem would get worse after sitting for a few days.
Check to make sure the air filter is not clogged; check for cracks, gaps, or holes in the black plastic tube between the air filter housing and throttle body, and check the idle air control valve to make sure it is not gummed up and moves freely. The IAC is what I think the culprit is.
Hey, Ray, in cases like this won't the check engine light come on? If so, can't Gib just hook up a code reader and see what codes his car is throwing? jor
The OP did not mention a check engine light, and the first generation OBD does not monitor most of that stuff. If there is no check engine light illuminated, it is unlikely that any codes will be stored.
A bad fuel pressure regulator will usually fail to maintain fuel pressure. A bad fuel pressure regulator will result in long crank times when starting cold. This is the opposite of what the OP is describing. Fuel pumps don't go bad that often, and they usually do not recover after sitting for a while.
I'm replacing the fuel filter anyway, since it's overdue and I can easily do it.
How do I locate the IAC? I have the Haynes manual for 83-90 Camrys (for a previous one I owned), but it doesn't mention the IAC. It does show an ISC valve (idle speed control), but checking this seems to need the engine running. Should I just remove and clean it?
Also, regarding the engine check light, does the engine need to be running for this to convey something? I ask because the orange engine light does come on when I switch the ignition on.
By the way, thanks to everyone for helpful advice.
I replaced the fuel filter, and to my great surprise the car started and ran. Time will tell if the problem is really fixed, but the indications are good. Thanks again.
I thought that was too good to be true. I let the car run for a while until hot. At this point it seemed to be running fine at normal driving revs, but the idle speed was wavering between about 900 and 1000 rpm. After stopping, it didn't want to start, then it did start and I noticed that this time the engine check light stayed on for a second or so after the engine was running. I stopped it and immediately tried to start again. No luck.
Would it be a good idea to remove the throttle body, then take the ISC valve off and clean it? Any major pitfalls here?
Myself, I wouldn't at this point. I think most of that can be cleaned on the car with carb cleaner, etc. It's possible the engine is loaded up with carbon. But.. In that case, it will usually run fine until it warms up a bit. Then it quits due to lack of compression. The carbon on the intake valves will slightly expand when it gets hot, and keep the valves from fully closing. When that happens, you will usually notice the starter motor spinning faster than usual, or irregular. But it sure would cut a lot of guesswork to know the fuel pressure. I had this exact scenario on our 92 camry, and I made my own pressure gauge using a sawed off bolt that would fit the banjo connector. You have to drill a hole through it, and then you clamp a hose to it. I had a fairly long hose and could bring the gauge in the car with me when I was driving around. :/ In my case, the fuel pressure was hunky dory.. Ours was ultra carboned up on the intake valves, and injectors. The way I cleaned it out was to #1 add a bottle of techron to the gas. Then I mixed techron and carb/injector cleaner right into the intake on the vacuum ports. I'd spray the heck out of it, let it run until it quit, and then let it sit for about and hour so it would cool, and the valves would close back up. Then I'd do it again.. Over and over until clean. I finally got it all out. You can also buy flush kits, and motorvac, etc if you are in a hurry.. Techron works after the engine gets hot, and then sits. It does very little while actually driving. But I think it's about the best crud buster you can get that can be bought at nearly any store. You may well have some other problem, but just mentioning this, cuz they don't like being carboned up and will quit running when it gets hot. Heck, you might be having some kind of ignition problem.. :/ It's hard to guess on the internet. MK
As I mentioned before, I didn't think a fuel filter would solve the problem because the fuel filter normally lasts the life of the vehicle, unless you often buy the cheapest gas you can find from a place that sells poor quality fuel.
Others are suggesting that the fuel pump or fuel pressure regulator are bad, and since you are getting fuel delivery when you first crank the car, there is a 99% chance that they are good.
I don't remember when Toyota changed from ISC to IAC, but they serve the same function - allow air to bypass the closed throttle plate. Try spraying carb cleaner on the ISC to free it up. You may be able to clean it without removing it from the throttle body.
It's hard to find bad quality gas here. The Haynes manual recommends replacing the filter every 30k miles, but that doesn't mean it's really necessary.
Agreed. Since the car runs well once it has properly started, it's clear that the fuel is being delivered OK.
I see there is quite lot of black sticky deposit in the throat of the throttle. I guess I do need to remove the throttle body to have a good chance of cleaning the ISC, right?
You know, I've had this car for almost 11 years, and this is the first time I've had any trouble with the engine. Great car.
IMO, 30 K miles is overkill for replacing the fuel filter.
Just spray some carb cleaner into the throat of the throttle body and wipe it out with a rag or paper towel. Open the throttle plate and spray the back side as well, paying attention to where the rod that the plate pivots on passes through the throttle body. Somewhere near the throttle plate should be the ISC. I think you can remove it without having to remove the entire throttle body.
The car will run poorly and smoke a lot the first time you start it after you clean the throttle body, until the carb cleaner burns off.
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