1998 LX470 dies after three seconds (1 Viewer)

[FurtiveJupiter]

Hello all! I have a 98 LX470. I got it a few months ago and have been having this issue where when I turn the key it cranks up, starts, and dies after approx three seconds. I have changed out the fuel pump, fuel filter, throttle position sensors, and MAF. I thought it could be related to the immobilizer, but have concluded that if it was the immobilizer it wouldnt crank at all. Correct? Im really trying to figure this out and am at a loss. The battery has been replaced and on a tender. I guess it could be the crank sensor? I dont want to just keep throwing parts at it. Does anyone have any ideas?

Thanks!

 

[MechE30]

Immobilizer will crank but not fire, even for a second, so I do not think that’s your issue. When it runs for those few seconds, is it stable (all cylinders firing) or seem off?

 

[SteveH]

No codes, either showing or latent?

 

[FurtiveJupiter]

Immobilizer will crank but not fire, even for a second, so I do not think that’s your issue. When it runs for those few seconds, is it stable (all cylinders firing) or seem off?

seems stable, then sputters and dies.

No codes, either showing or latent?

nope nothing. ill check again today. but last time I checked I didnt have anything.

 

[nissanh]

Timing?
Do you see a steady RPM in that 3 seconds or bounces up/down?
Could it be the cam sensor that cuts off the engine? May be the cam sensor is loose and does not have the correct air gap? Its a variable reluctance sensor and must be at the right distance to cam to produce the amplitude needed. It is located on driverside cam housing. Check for wire integrity.

 

[MechE30]

Yeah if you recently had the timing belt or water pump replaced they may have routed the cps wire incorrectly. It’s fairly common and an easy mistake to make.

 

[Mike NXP]

nope nothing. ill check again today. but last time I checked I didnt have anything.

Might not be a huge help but maybe a video from under the hood during the start up and dying would help some folks narrow it down.

>> So this issue has been going on ever since you purchased the truck
>> Did the previous owner mention anything?
>> Can you put the VIN into Toyota Owners and try to get service history

Timing?
Do you see a steady RPM in that 3 seconds or bounces up/down?
Could it be the cam sensor that cuts off the engine? May be the cam sensor is loose and does not have the correct air gap? Its a variable reluctance sensor and must be at the right distance to cam to produce the amplitude needed. It is located on driverside cam housing. Check for wire integrity.

Where is this located at for OP to check? Any pics?

 

[Mike NXP]

If the cam sensor wire becomes relevant I think this thread might help
And these wires go to...........? - https://forum.ih8mud.com/threads/and-these-wires-go-to.1136581/

>> But wouldn't this throw a check engine light?

 

[FurtiveJupiter]

I FIGURED IT OUT. I feel so stupid. It was a 10A fuse... The IGN fuse in the drivers side kick panel. runs perfectly now. Thanks for the help you guys!

 

[riffman12]

glad you got it figured out! but I wonder why it blew in the first place

 

[Malleus]

That's always the right question to ask.