Camry 2002 stalls after start: TPS?

[celerix]

Hi everybody. My 2.4l camry 2002 dies right after start. This usually happens with cold starts. I checked multiple threads with similar problems and I have narrowed down the possible culprits. My working theory now is that the TPS or throttle body may be bad. Could I get answers to the following?

1. Is the throttle body fully closed at rest? Mine opens a bit.
2. With ignition at ON (engine not started) my TPS reads 17.6 on my Actron scanner. Is this figure OK?


OTHER THEORIES
The only code I ever got is 1656: OCV circuit malfunction. A technician checked and said it was caused by a poor grounding. That code has not returned since then (a few days back). However, I'd still place OCV on the list:

1. Bad OCV/circuit/ECM (shudder!)

2. Leak in air throttle after MAF (VSV for EVAP stuck open?)

3. Bad A/F sensor

Help! I'm getting old fast...

[LoudCamry]

check your battery.

My aunti car start and die right after, I replace the battery and it don't die anymore.

[dave0919]

Battery or vacuum leak are your best bet, Check the hose ends fro cracking (don't froget the 2 above the PS pump) also clean the TB with carb spray

[fenixus]

are there any trouble codes (even pending) stored in ECM ? is Check Engine Light on ?
does engine speed jump up to e.g. 1,500rpm on cold start and drops to normal speed after warm up ? when exactly does the car die ? how does it die ? any shaking for a few seconds (e.g. too low RPM, not enough fuel, vacuum leak, etc.) ?

[celerix]

Thanks all.
Fenixus: The 1565 code turned up again this morning (more on that later). Apart from that, there's 1135: Air Fuel Ratio heater circuit. But that is because when starting causes so much problems, I sometimes disconnect the A/F sensor so the EFI will work in open loop. This seems to keep the engine on.

To answer your other questions: In the morning or after the car has been parked for some time, when I start it, it cranks and starts (RPM gets to around 1500 in the mornings) but instantly, the rpm drops straight down and the engine stalls. No shaking, as I expect it to do with air leaks; it just dies. If I do this for around 10 - 20 times, the engine finally starts and stays at around 700rpm (I'm guessing this has something to do with the fact that the engine temperature would have increased).

I have done a few tests on my Throttle body and long and short is, I no longer think its the prime suspect, especially since as I said above, the OCV malfunction code came up again. Although I cannot see why an OCV malfunction would present a problem with idling with the A/F sensor connected, but not when it's disconnected, I have investigated today.

I found that the cables between OCV and ECM are good. OCV seems OK. Resistance is 7.9 ohms. Inspecting it shows no gunk. Applying 12v, the solenoid moves smartly. HOWEVER, on checking the signal from the ECM, I found that it is a pulsetrain with pulses of maximum voltage of around 1V. From the manuals, I believe the amplitudes should get to 10V or thereabouts.

So my new theory is that the ECM is supplying signals that would not allow the OCV function properly. I do not know why this would make the car stall only when the A/F sensor is connected but based on the premise that the measured signal voltage is too low, I conclude that the ECM (or at least the OCV+ ad OCV- pins) is bad. I hope to get another ECM before Friday to test this theory.

In the meantime, I would really appreciate your insight.

[fenixus]

have you tested the resistance of A/F sensor ? since it stall with sensor connected and works without it, it makes me thinking that it might be the culprit.

P1135 came on probably because you disconnected A/F sensor during engine operation (P1135 is A/F Sensor Heater Circuit Malfunction Only for California Spec.) or maybe this sensor doesn't get heated up by heater and sends crap signals to ECM on cold start ? just shooting some ideas...

I cannot find toyota specific explanation of P1565, but from google (VW car though) it looks like "P1565 - idle speed control lower limit not attained.", so that would somewhat point to sticky IAC valve in Throttle Body or maybe TPS acting up during cold start up ?

I cannot find exact Diagnostics factory manual for gen5 camry, but look through those, maybe you will find something that rings the bell:
http://www.camrystuff.com/index.php?page=Gen5_Manuals

[BlackCamSe]

sounds like a dirty/faulty MAF sensor to me.

[fenixus]

4cyl engines don't have MAF, only MAP. good idea about testing it too or at least checking vacuum lines for leaks .... though vacuum leak usually causes engine hiccups for a second or two before dying ...

[BlackCamSe]

Originally Posted by fenixus

4cyl engines don't have MAF, only MAP. good idea about testing it too or at least checking vacuum lines for leaks .... though vacuum leak usually causes engine hiccups for a second or two before dying ...

the 2AZ does have a MAF.....right after the air box.

[fenixus]

Originally Posted by BlackCamSe

the 2AZ does have a MAF.....right after the air box.

ahh, sorrry, i was thinking about 5s-fe ... my bad ... hehe. always learning something new, thanks!

[BlackCamSe]

Originally Posted by fenixus

ahh, sorrry, i was thinking about 5s-fe ... my bad ... hehe. always learning something new, thanks!

i figured u were talking about the 5s, seeing that you have a 2000 solara. Those engines are very well built

[fenixus]

Originally Posted by BlackCamSe

i figured u were talking about the 5s, seeing that you have a 2000 solara. Those engines are very well built

yeah it seems so. no major trouble so far, power output is still good as new. only thing that annoys me is intake/exhaust valves that are not hydraulic and need periodic check and adjustment by replacing shims ...

[arturchik]

Hi guys, I have the same problem with my 2002 Camry, 4 cyl. It starts up, works for a 30 sec. and then dies.
after couple of tries it wont start at all, until it cools down for half an hour. It also gives me a p1565 code, which is the (OCV cirquit malfunctin) I have replaced the OCV sensor, and still the same thing. still dies after 30 sec of run. Still gives me a p 1565 code. I have replaced all engine sensors, I gave up. PLEASE HELP.

[celerix]

Hello guys. Some updates: The problem persists. In recent weeks, I have disconnected the AFR sensor entirely, forcing the car to work in Open Loop. In this state, the stalling-after-cold-starting problem disappears. Come to think of it, other than a P1135 DTC, the car has not had any other problems.

I'm not happy about leaving the car running in open loop though, so I'm still chewing on the problem until I get a new theory to test.

Reading some other posts where engines stall on cold start, the EVAP system could be at fault here. I already checked the VSV for EVAP and it seems OK. Next, when I have time, I intend to check out the Charcoal canister assembly and the VSV for Pressure Switching Valve (primarily because of this post http://www.toyotanation.com/forum/ar.../t-199225.html ).

[arturchik]

Hello everyone, please help if you can. My 2002 camry 2.4 stalls after cold start, the engine revs to 1500 rpm and stalls, after 15 tries it finally runs. I also noticed that my OCV relay is clicking like crazy, and when temp goes up high enough to kick the cooling fans in, the cooling relays also are clicking. Sometimes I get a P1565 code. I also noticed when I disconnect the cable from throttle body, my car starts cold and stays on.