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Solenoid/Switch? on '84 6.2 Blazer vacuum pump

cornemuse

cornemuse

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Location
San Diego county
On my '84 6.2 diesel, the vacuum pump (diaphram) went out. The pump has a switch/solenoid? on the body. Are the actual diaphrams (two bolts mounted) interchangeable? How necessary is the solenoid/switch? What is it for anyways? The GM dealers/O'riellys etc. dont carry it, here, anyway.
Thanks,

-corne-

(I have another pump w/o the 'switch' for diaphram swapping if they are swappable, otherwise, , ,)
 
The pump will interchange.
Is the solenoid your seeing actually the ESS? if yes you need it.
 
Whats "ESS"? the wiring goes to smog switches/valves?? on driver side firewall. Car had originally a '700 r 4' trans, was replaced with t 400. The electric positioner?? on governer was swapped with a vacuum regulator(?). The electric unit was/is plugged in & is laying 'under' the gov/manifold. <-was like this when I bought it 15 years ago.
 
ESS = Engine Speed Sensor. Rather than using a signal off of the alternator, some engines have a taller oil pump drive with a two wire connector on it.

Can you take pics of the parts you're referring to?

And when the th400 goes out, IMO a 4l80e w/ stand alone control from Leroy would be a good move. Stronger, longer lasting, and OD saves fuel...
 
I looked in a shop manual, it is the 'ess'. Thr manual shows it in '6.2 diesel' in engine section & 6.2 in smog section. Does not show it in trans section. Apparently its just for smog. It also turns out my '84 Blazer is actually an early '85 sold as 84. My 84 suburban & 82 PU dont have ess on the vacuum pump housing. Also, no one has either the complete unit or just the diaphram unit itself. The older diaphram connection tube hits the ess part of pump, & cant be swapped.
 
Actually you have a Communist CARB emissions issue... The OEM's experimented on (you) CA's early emissions by releasing emissions in CA first and then the next model year would get the updated emissions for everyone else (Federal Emissions.)

Big question: do you still have to pass emissions with it?

No? - Remove SES lamp, plug EGR vac line, Plug off EPR vac line. Use any vac pump that will fit.

Note: TCC lock up, if you have it, may be controlled by this computer.

Yes:

So your 1984 IS a 1984, but a CA emissions 1984. Hopefully using 1985 parts (Looks like it was used up to and on 1989 R/V series as well) will help otherwise you got to match part numbers and last resort at a GM dealer parts counter. Best I can tell is the primitive emissions computer info is rare to find. It controls the EGR and EPR, Exhaust Pressure Regulator, only. The EPR is a valve on the driver's side manifold that flows exhaust through the intake to heat it up and possibly flow more EGR.

Your best way to tell is a lack of a Service Engine Soon bulb on the other rides. This bulb is a separate add in assembly on the lower left of the dash.

Last time I ran into this was an electronic EGR valve on a 1993 4.3L TBI CA emissions pickup outside of CA. 1993 Federal emissions everywhere else was vacuum controlled. It took two weeks to get the GM part and it was $150 more than the vac controlled part. Only 1994 would show the correct part at the Colorado dealer.
 
WarWagon said:
Actually you have a Communist CARB emissions issue... The OEM's experimented on (you) CA's early emissions by releasing emissions in CA first and then the next model year would get the updated emissions for everyone else (Federal Emissions.)

Big question: do you still have to pass emissions with it?

No? - Remove SES lamp, plug EGR vac line, Plug off EPR vac line. Use any vac pump that will fit.

Note: TCC lock up, if you have it, may be controlled by this computer.

Yes:

So your 1984 IS a 1984, but a CA emissions 1984. Hopefully using 1985 parts (Looks like it was used up to and on 1989 R/V series as well) will help otherwise you got to match part numbers and last resort at a GM dealer parts counter. Best I can tell is the primitive emissions computer info is rare to find. It controls the EGR and EPR, Exhaust Pressure Regulator, only. The EPR is a valve on the driver's side manifold that flows exhaust through the intake to heat it up and possibly flow more EGR.

Your best way to tell is a lack of a Service Engine Soon bulb on the other rides. This bulb is a separate add in assembly on the lower left of the dash.

Last time I ran into this was an electronic EGR valve on a 1993 4.3L TBI CA emissions pickup outside of CA. 1993 Federal emissions everywhere else was vacuum controlled. It took two weeks to get the GM part and it was $150 more than the vac controlled part. Only 1994 would show the correct part at the Colorado dealer.
Click to expand...

All I needed to know!!! Thanx!! Never smogged any of 'em.

(I do not have SES lite on this (on none of 'em) vehicle)

-c-
 
TCC lock in the transmission would be the only concern and I am not sure if you have it and how it works. Does it need that sensor for the primitive computer to lock the TCC? Plugging the EGR vac line on our 1988 only turned the light on and the TCC continued to work.
 
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