[bigmelon]

Hi Everybody,

New user here looking for some help/advice with narrowing down the problem with engine start-up.

Background. My friend's Toyota has problems with starting and I'd like to fix the problem but I have no experience with Toyotas (did a bit of repairs on my old Ford Mondeo).

Problem. Current state is that the car cranks but will not start, except the "first" time (after some break? Cold engine?) when it will run irregularly for few seconds (3-4). There's no Check Engine light on, battery is almost new, ignition cables have been replaced and spark checked.

How it all started. I hope I remembered the story correct: I was told that some time ago (2, 3 months) someone started driving the car with a rapid jerk (how's that possible? High RPM + hand break?), since then car didn't run the same, as time passed it seemed to not get any better. At some point, after a heavy rain, the car started to have problems with startup and would run irregularly.

I went through this forum and found possible reasons that I would like to check (I just had a brief look today):

1. IAC Valve
2. Skipped timing belt - how to verify?
3. Problems with fuel supply - fuel pump (power supply, relays, etc.), proper pressure
4. Grounding problem
5. Clogged EGR
6. EFI relay
7. Fuel safety switch (is there one?)
8. Disconnect battery, wait, reconnect?

Is there anything else worth checking? I cannot somehow connect all the parts of the story. Could a rapid start/driving cause skipping of a timing belt? But then the car was still running correctly.

Car is Toyota RAV4 1999, gasoline, 4WD, automatic gearbox.

Any suggestions greatly appreciated.

 

[Pugbath]

Hey big melon,

I've found the most common causes of a crank no start are:
-no fuel
-no spark
-low compression

You said the vehicle has spark, but have you verified that you are getting spark out of both coils and at all four plugs? If yes, check to see if you are getting fuel pressure to the rail. (don't remember if there is a valve or not, but you can loosen the bolt to the banjo of the fuel line to verify that you are getting fuel to the engine.)

If you are getting fuel and spark, pull the plugs and check for compression with a compression gauge.

To answer your question about checking timing, you could pull the upper timing cover, rotate the crankshaft to TDC (0 mark on the lower timing cover) and see if your cam gear timing mark is aligned to TDC. (if it is off at first, rotate engine to TDC again as your crankshaft may be 180 degrees off.)

Hope this helps!

 

[Elle_Rav4]

-- See if any check engine light codes are stored.

-- A skipped timing belt; failed timing belt tensioner; or similar is entirely possible. Along with Pugbath's suggestion, maybe read the guidance at https://www.rav4world.com/threads/died-while-driving-wont-start.294917/

-- Any idea when the timing belt was last changed?

-- Go to https://cardiagn.com/ignition-99-camry/ . Skim through pages IG-1 to IG-11. Do the resistance tests for:
Camshaft position sensor
Crankshaft position sensor
Ignition coils

(The 99 Camry has a 5S-FE engine whose ignition parts and related sensors have the same tests and same, or nearly the same, locations as your Rav4's 3S-FE engine.)

Youtube also has videos that show where the crankshaft and camshaft position sensors are on your Rav4.

-- Check the ECT sensor by unplugging its pigtail and measuring its resistance:

Is the resistance consistent with the graph below?

-- Make sure your battery stays well-charged while you troubleshoot. Else a low battery causes starting problems on these Rav4s.

 

[bigmelon]

Thanks for all the suggestions! L.

 

[Techsus]

Again, immediate thought on "Crank No-Start on Warm Engine:"
R&R Engine Coolant Temperature Sensor immediately. Install OEM-only Toyota Sensor. Hope it saves you more grief than what I went through, getting stranded near 5 p.m. on a Friday.

 

[Techsus]

@bigmelon

What progress have you made? Closure is key to our Threads, "for the Common Good."