Engine slow cranking

[Ivanprado90 Junior Member Find all posts View Profile Close Ivanprado90]

So my engine has slow cracking even when hot, and to be honest it has a better start when cold. if the engine is running and i turn it off , then turn it on, it will have a slow cranking.. i have checked the starter, had it opened and tested, the contactors were changed and the starter was cleaned, after that it had a better sound. also did an engine compression test, test came fine nothing to worry about. glow plugs are in perfect condition also.

That leaves me only with diesel, i have checked the fuel lines for any sign of leak, changed diesel primer pump and filter.

My final guess is the injection pump...... maybe the pump has low pressure? that is causing my engine to have slow cranking? of maybe the pump seals are bad? how can i test the pump? can anyone give me any input. would appreciate it tons

[RanJ Avid PP Poster! Find all posts View Profile Close RanJ]

Has the battery been load tested recently?

[Ivanprado90 Junior Member Find all posts View Profile Close Ivanprado90]

yes, it tested good, i have a high amp battery

[Bear63 Senior Member Find all posts View Profile Close Bear63]

Volt drop and currant draw when cranking needs to be checked

[Ivanprado90 Junior Member Find all posts View Profile Close Ivanprado90]

a new thing, so yesterday i left the fuel level reach the reserve tank, the light came in and went to the gas station and filled the tank to the top top. after i did that i have been getting a perfect cracking timing, and start up. i am still testing it to see if i get it again. maybe the system had some air and when the fuel level went low and i refilled it to the top the air got out? it is weird

[Ivanprado90 Junior Member Find all posts View Profile Close Ivanprado90]

Hi all, so the slow crancking is back and my personal diagnosis is fuel related, today i had my injectors taken out to see how they were. In general they were ok, took time to clean and calibrate them. turned the engine ok, but after i turned it off for 1 hour issue came back, so its still here. What other recommendations do you,suggest me? Next im going for the injection pump, my feeling is that the pump is loosing pressure maybe? Plz help also are they any sensors i should be aware of that may cause engine slow crancking after few minutes off?

[SWR Banned Find all posts View Profile Close SWR]

Gday Ivanprado90

So my engine has slow cracking even when hot, and to be honest it has a better start when cold.

As the starter motor is heated up (Exhaust/ engine bay heat) then so is the resistance and current draw!

The average current draw for a typical 4 cylinder diesel engine is in the region of 200 to 300 amps.

If the starter motor is on its way out this current draw will be much higher and eventually prematurely kill your battery due to distorting the plates in the battery.

I personally do not know what the actual correct current draw for the starter motor on your rig is when the starter motor is in its healthy state but it sounds like your starter motor is shorting/ Breaking down as the fuel pump/ injectors can not effect the starter cranking speed?

Get a sparkie to check what the actual current draw is on your starter motor and make sure that the earth strap to the body and engine are a good earth!

Cheers

[OziOffroad Senior Member Find all posts View Profile Close OziOffroad]

after i did that i have been getting a perfect cracking timing, and start up

I'm going come at this from left field and ask if we've mixed up your problem;

Is it cranking over slower when hot (starter very low RPM) or is it cranking for a longer time before it starts when hot? (ie; hard to start hot)

Mick

[Ivanprado90 Junior Member Find all posts View Profile Close Ivanprado90]

The second one, It is crancking slower and for longer time when hot.. One fact to take in consideration which i had not said yet is. That i bought a 1kzte year 2005 (intercooled) that was in a 120 series that crashed. So i have a 90 series with, older 1kzte. when the swap was done some mods had to done and parts had,to be switched from one engine to another fpr example i had to stay with the old injection pump cause the one from the 120 series would not fit in, had to use the same crank and some other things. So question is maybe the engine not having its corresponding injection pump and having an older version one maybe the pressure on this old pump is not enought or something like that for the engine? Just a crazy thing i came up with.

[Ivanprado90 Junior Member Find all posts View Profile Close Ivanprado90]

When it does it when hot it would not start at the First crank but it does at the second one

[OziOffroad Senior Member Find all posts View Profile Close OziOffroad]

OK, so I take it you're not in Australia?

Have you checked for fault codes?

Mick

[Ivanprado90 Junior Member Find all posts View Profile Close Ivanprado90]

No, i am from dominican republic, can i check for fault codes even thought the check engine light has not turned on? Will it show any errors anyway?

[OziOffroad Senior Member Find all posts View Profile Close OziOffroad]

No, i am from dominican republic, can i check for fault codes even thought the check engine light has not turned on? Will it show any errors anyway?

Yes, the dash light only comes on when the ECU is ignoring a major sensor and is running a lesser managemant map or it's in limp mode. This is usually a complete open or short circuit detection.
Intermittent faults are still logged ad so are sensors reading out of range (High/Low readings)

You can extract the codes manually by shorting two pins in the DLC connector as reading the codes from the flashing dash light. (There's a tread on here somewhere on how to go about it)

Or you can use Techstream (Toyota's Software for accessing their ECU's and easy enough to source)

Mick