New 87 lj71 owner and issues (1 Viewer)

[EvenMorehj60]

Hey there everyone I hope I'm posting I the right place please inform me if I'm not. I'm recently purchased a 1987 LJ71. It's pretty sluggish but for the most part it's in amazing shape. To over come the sluggishness I put a 2.5" exhaust, I lost power at highway speeds and the orange light on my turbo display on the dash comes on sooner. I tried to counter the exhaust with a new intake and egr delete I have much more powerful but still have issues maintaining speed up hills on the highway and the orange light comes on quickly. What does the orange light mean? Would creating more back pressure from a smaller exhaust help? Can anyone share similar experiences? Can anyone share links to repair manuals/partslist for the body? Thanks, sincerely a neub.

 

[Cavalier2000]

If I remember right that engine has about as much power as a blender.

Are you still at factory boost? And your exhaust. Did you just change the muffler or from the turbo back?

 

[Mr Tibbs]

Orange light is the overboost light, you are pushing the engine to it's limits. If you really need to go that fast you need a different vehicle. I have never seen the over boost light come on in the wife's BJ71.

 

[EvenMorehj60]

If I remember right that engine has about as much power as a blender.

Are you still at factory boost? And your exhaust. Did you just change the muffler or from the turbo back?

Still at factory boost, I went 2.5" from the turbo back with a muffler, yes you're right not a powerful engine but it didn't over boost and could maintain speed up hills before the mods, now I have more power at lower speeds but 50mph+ I feel I have less power and it over boosts as soon I accelerate.

 

[AirheadNut]

I never saw the over boost light come on until I replaced my turbo with one with the wastegate set at around 15psi. I don't think that a free-flow exhaust should make it over boost, but I could be wrong. You will want to read this thread, it has a TON of information.

Ideas for improving the 2LTE

Sweet truck by the way, got any more photos?

 

[EvenMorehj60]

Orange light is the overboost light, you are pushing the engine to it's limits. If you really need to go that fast you need a different vehicle. I have never seen the over boost light come on in the wife's BJ71.

OK even when everything was stock it would come on at the higher rpm Range. I rarely push it beyond 60mph it have trouble maintaining that without overboosting up hills.

 

[EvenMorehj60]

So what I've learned, freeflow exhaust gets rid of backpressure which allows your turbo to spin more freely which allows it to boost higher, adding an intake did not help build up that back pressure but it did add amazing power. I can add a restrictor plate or smaller section of exhaust to put back some backpressure or add a boost controller to overcome the overboost. Ill be reading up on the wastegate now an probably modifying or replacing it. Any tips or advice? Here's a great link I wish I read before spending money on exhaust/intake this guy finds that free power in his 2lt and has a technical writing background.

Toyota 4WD Surf Owners • View topic - 2LT Boost compensator

 

[EvenMorehj60]

At your request a few more pics, imported from Japan.

 

[Gun Runner 5]

At your convenience .....
U.S. 70's Registration.

 

[GTSSportCoupe]

Still at factory boost, I went 2.5" from the turbo back with a muffler, yes you're right not a powerful engine but it didn't over boost and could maintain speed up hills before the mods, now I have more power at lower speeds but 50mph+ I feel I have less power and it over boosts as soon I accelerate.

It probably is boosting more than stock after the work you've done. Most likely, you need to adjust the boost compensator on the top of the injection pump to suit the change in boost/air into the engine. If there is too much boost, it pushes the fuel pin in to a point where the pin starts cutting fuel back again. By tightening the spring in there a few clicks, it will resist the added boost, and the fuel pin will better match your boost curve. Just go read about tuning boost compensators on rotary Denso pumps and you'll see what I mean.

You should also buy a manual boost controller (and a boost gauge if you don't have one) so that you can have better control of the maximum boost. I'd recommend 12psi or so with no intercooler, or up to 15psi with an intercooler.

Nice clean truck, hope you enjoy it.

 

[clintnz]

...plus just have a good check through all the turbo plumbing, wastegate etc. The turbo warning light coming on when it was stock means something isn't right - I've driven a bunch of different turbo diesel Toyotas & never seen that light come on while running.

Cheers
Clint

 

[EvenMorehj60]

Thanks for all the help I've been reading up the on the Denson pumps I'll read up more on them. I have checked all the vacuume tubes they are all in good shape, the wastegate actuator arm moves with some resistance, as I imagine it is supposed to. Ill try spraying out the wastegate actuator with parts cleaner and test some of the check valves.

 

[EvenMorehj60]

I just tested my actuator on my turbo, air bubbles were forming where the red is circled, is that the source of my overboost issue? Can anyone else blow in the tube to the wastegate actuator and let me know if it holds or allows air to blow through? Thanks!