Help - '96 LX450

[tucker74]

Just got a call from my friend who is in route from Houston to Austin and his LX is cutting out every time he hits a bump. The truck has 140k but new cap, rotor, wires, plugs, fuel filter and intake hose. Didn't know what to tell him - mentioned the EFI relay ... but then just searched and that was FJ80s. He said the CEL came on but is flickering - engine cuts out (spudders, RPM drop) but then recovers.

I told him to pull off and have the code read at the next town - all fluids/gauges normal. Any ideas?

Tucker

 

[woody]

if he JUST replaced those items, my first guess would be either one of those didn't get seated properly or he bumped someothing else in the process and is getting an intermittant connection.

 

[tucker74]

if he JUST replaced those items, my first guess would be either one of those didn't get seated properly or he bumped someothing else in the process and is getting an intermittant connection.

Sorry - I meant in the last 20k ... I was just eliminating where I had already gone in trying to help ...

My other thought was bad gas - but the bump thing kinda throws that out.

Tucker

 

[sjcruiser]

Loose ground (from battery to chasis) maybe?

 

[sixsracing]

While the truck is running lift the hood and just touch all the wires on or around the intake manifold, distributor, a/filter assy etc. He'll find it in no time.

 

[tucker74]

While the truck is running lift the hood and just touch all the wires on or around the intake manifold, distributor, a/filter assy etc. He'll find it in no time.

He tried this w/o any luck - he said the coil wire shocked him though (is this normal when grabbing near coil w/ engine running?).

Only seems to happen when then engine in "D" - some sort of vacuum leak?

Tucker

 

[sjcruiser]

He tried this w/o any luck - he said the coil wire shocked him though (is this normal when grabbing near coil w/ engine running?).

Only seems to happen when then engine in "D" - some sort of vacuum leak?

Tucker

I was about to warn to not using bare hands

All the wires are insulated/shielded; so if it shocked him, it may shorted against the chasis going over bumps.

 

[sixsracing]

He should not have been shocked by just grabbing the coil wire. If he pulled it out slightly it may do that.

If it's only happening in drive then something is tight (wire/vacuum line etc.) and when the engine moves slightly under torque it's putting pressure on the issue. Air boots are a common problem with engine torque. So are wire harnesses. If he cannot get it to do it at idle he may also have a fuel pump or pressure regulator on it's way out. Did he take the cover off of the relay box and jiggle the relays? Particularly F/I and ignition.

 

[tucker74]

He got the code pulled at Auto Zone - came back TPS sensor ... or more specifically cam throttle position sensor? Anyone?

Tucker

 

[elmariachi]

Just got a call from my friend who is in route from Houston to Austin and his LX is cutting out every time he hits a bump. Tucker

Sounds like the coil wire not properly seated. <<<Scratch that>>>> Tell him I live NW of Houston of off 290 to Austin if he winds up in a jam....832-620-5419.

Jim

 

[Rookie2]

Loose ground (from battery to chasis) maybe?

Just curious, but would this cause a running engine to cut out? I thought once the engine was running, the alternator runs the eletrical stuff in addition to keeping the battery charged.

 

[sjcruiser]

Just curious, but would this cause a running engine to cut out? I thought once the engine was running, the alternator runs the eletrical stuff in addition to keeping the battery charged.

That's surely the case with the + terminal...

 

[Riley]

Check the wiring loom on the firewall at the rear of the engine. That wiring gets hot and after a lot of miles it can start to short out. I've heard of this happening when in drive due to torque on the engine.

 

[cruiserdan]

Check the engine harness where it passes by the EGR valve. My bet is there is a problem there and when the engine torques over it is opening up a fried wire.



D-

 

[Beowulf]

>> new intake hose. <<

Combined with TPS sensor OBD-II code would tell me to start with what he did with the intake hose. May be a loose connection.

-B-

 

[tucker74]

He made it home last night - plan is to start with the TPS sensor and then secondary sensor if that doesn't work....

I read Junks post last night - I'll tell him to go through the wiring harness too -

Tucker

 

[sixsracing]

Continuity test on the wiring harness first may save him a ton of money and frustration.

 

[tucker74]

Ding ding - we have a winner!

Check the engine harness where it passes by the EGR valve. My bet is there is a problem there and when the engine torques over it is opening up a fried wire.
D-

Melted wiring harness on the EGR - Toyota wants $500 to repair (and re-route so it won't happen again). Guess that's better than $2k for a new harness and install

Thanks guys -

Tucker

 

[wob]

I've been through the same thing.

 

[sixsracing]

Better $500.00 and fixed than multiple non-returnable purchases from the dealer that didn't fix it.