EGR woes

[metrotech]

i too myself have had plenty of problems with my egr system, to explain your different readings when the egr vacuum line is t'd into. you basically have 6 inches of vacuum without the egr conected, now if you t into that line and split the vacuum you will split the reading.by the way this system work just off idel and there is no need to drive down the road to perform and tests on it. I ran into the same problem with the my tbi, i blew air through it after cleaning with carb cleaner. perhaps it was part of my failing transducer. either way i got it cleared up. still had a code 51 for about the 10th time. so i took the valve off, high revs came shortly after. but i knew i had good flow( intake vacuum and exhaust pressure). so now knowing this i looked at the valve itself. sure enough black and nasty.As they all are. to what extent u never know till u scrape all that carbon out. penitrating lube is best on this application, and after install so far so good.

[jtgh]

yes, that running test is only on 94 and newer, for sidekicks,
running with wheels spinning test. is a real pain those with newer kicks.
on metros, not sure.

yes, the valve main is #1 clog.
also , it is a rumor that the egr only flows thru one path on one cyclinder on some metros.
and this can cause the valve to go bad, if egr is bad.
might not be all years.
or is it that paths get blocked in manifold and all egr goes to one cyclinder and not 3.
cant remember but they said , this is common on metros.

cheers.
and hope yours purrs allong good,,

jerry

[Isuzuzuki man]

Just a note, don't know if it has been mentioned, the vac to the canister and EGR are ported, meaning they are before the throttle plate, so vac is modulated by the throttle plate, meaning at idle no vac will show, open the throttle and the vac gauge should jump.

[cjmike]

Just a quick note have you tried taking the egr valve off and starting the car?If it starts i bet you have a plugged passage from the right hand port from the egr valve going "INTO" the intake!I just did this tonite!I spent all the money on everything [egr valve ,modulator etc} cleaning out the head and intake passeges to the egr valve.Works like a charm and i missed it when i had the exhaust manifold and egr valve off earlier!Mike

[metrotech]

yes i had both pressure and plenty of vacuum, but since my egr solenoid was gettin close to marginal ( 35 ohms) i am guessing that is what will be the next to be replaced.

[jtgh]

no 35 is not marginal.
it can be AOK.
there is a wide range in the fsm , IIRC 20 -40 ohms?
i can look it up.
if it works when you apply power to it , it is a runner.
(not withstanding ,no leaks ,cracks,etc.)

its just a coil of wire, and the mfg machine can wind it + - extra turns do to its crude nature. It is also over designed, in that it has an extra margin of magnetic energy so that the thing will work when the battery is almost dead.
ECU will run down to 8v or there abouts.

i have have one car that dies at 10v. , not too friendly a car with bad battery.

that is a good question.

the fsm has all tests on the bench and on car for voltages and things like coils.

cheers.

[metrotech]

this information is incorrect people and i do appoligize for the previous posting.

the lowest voltage an ecm should or could run on is 10.5 volts.

as for the coil in the egr control solenoid, it is 25 to 39 ohms reswistance. once warmed up the coil may have much more resistance. once out of specification the code may appear. no ohms and it is shorted to gound, high resistance indicates that it had more resistance. being that i am in the upper range means that my egr isnt opening enough once the temp is high enough. which is when the egr functions. heat breeds resistance, resistance breeds heat. keep that in mind beacuse u may need it in the future. this is backed by 3 ase's electrical, engine performance and advanced engine performance.