Aquaduct (Automotive) Dec 29, 2004
Is this an 'engineering' forum or a 'how a cheapskate can ghetto rig a car' forum?????
<<Yes, it's an engineering forum. EGR is for NOx control. It <<decreases both power and fuel economy by displacing useful <<charge with burned exhaust gases.
Does egr...
patprimmer (Automotive) Dec 29, 2004
<<however if you re-tune without EGR you should be able to avoid detonation with suitable fuel and ignition timing.>>
Yeah....that would stop the engine from detonating... and making power... and getting good economy.. and running cool..
Retune for no egr...
Aquaduct (Automotive) Dec 28, 2004
<<OBDII also contains misfire monitors to look for the level of misfire that can kill catalysts. Usually in the range of 1-5%. >>
Misfires are counted and reported by the scantool as the number of misfire events per number of revolutions.
<<Your catalyst...
VinceA (Civil/Environme) Dec 28, 2004
<<why would it cause detonation?>>
EGR dilutes the air fuel mixture, quieting combustion temps and preventing spark knock, or detonation.
It couldnt cost more than a couple of hundred dollars to fix it right, why not just get it over with, especially if...
In a 1986 Toyota, the EGR is fairly important.
You may not notice anything for a while if you leave the egr inop. You may get a check engine light. You will spew NOX at a huge rate. You will get less mpg and you may slowly detonate the engine to death.
Ben
A couple of things...
The ECU needs to see the pre-cat 02 swinging between appx .2v and .8v very rapidly; and the post-cat 02 swinging from appx .4 to .6 very slowly so that it can verify that the cat is doing its job.
Cats on OABD-11 cars are finely tuned to the engine management system, and...
Wouldnt it be simple to use an automotive oscilloscope?
Is voltage and time enough?
There are little spark check rigs available (lisle, kd etc) at any good parts store that haved an adjustable gap scale.
I have seen newer cars throw a spark 3+ inches... makes a loud *snap*. The highest voltage...
This effet was well explained by Kevin Cameron in an article in Cycle World. The 'big bang' motors work because of tire deflection. On each combustion event, the tire carcas flexes then springs back. If they come too close together, the tire breaks loose. The trade-off was that the gp bikes...
