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Engine finally runs OK, but no real power!
#11
(02-10-2016, 12:20 AM)Zackman Wrote: Thank you so much for your time and detailed explanations.
YES! I agree that it is running rich; and occasionally (and I mean OCCASIONALLY) misfiring.
I will do the tests and will let you know of the result.
Unfortunately, we got a massive dump of snow last night, so everywhere is closed today! I will do the tests as soon as possible.

God bless you!
Zackman

great
the engine is good
so should be easy to find what's up.
http://www.fixkick.com
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#12
Hi FixKick:
In continuation of trying to see why the engine is running weak and misfiring, as suggested, I did vacuum test today. First, the line that goes to the orange color fast idle VSV got tested, and showed 17 inch vacuum.
However, there is no vacuum on the line that comes to and goes from the EGR VSV. Is this normal? I tried the bottom vacuum hose that goes to the throttle body; no vacuum! Then tried the top line that goes from the VSV to the P side of the EGR modulator; no vacuum either.
Is there supposed to be vacuum on those lines? If so, where should the vacuum be initiating from?

Thanks for your time in advance.
Zackman
[color=#800080][b]91 Sidekick JX, 8V, S. Carolina Car, 2 dr, 3 speed Auto Trani, Halifax, NS, Canada[/b][/color]
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#13
welcome back, and good luck with your car.
ok , the egr on that USA year, (not outside or has wrong ECU as many have)
uses these smog rule
the EGR is killed 2 ways, 1: idle switch closed, egr vsv dead and #2: the egr is ported vacuum at hose 27
this is normal
the main valve must not open until you accelerate, starting in about 1992 to 1994 (by ECU and cars VIN #)
the vsv will not open until rear tires are rolling, (vSS rules, veh, speed sensr)
what is important is the main valve is closed, at idle.

http://www.fixkick.com/sensors/8v-sensors.JPG

if the egr does open at idle, (bad ) it will misfire like crazy and even stall, in fact that is the stall tests seen here
seen here
http://www.fixkick.com/EGR-Gen1.html#Stall-test

hose 27 goes to ported vacuum, this port is dead at vacuum. due to complex TB internal porting, (both on 8v and 16v) same rule.
and mixing up hoses, is a bad deal here.
the egr is modulated with the mod valve , which used back pressure from the CAT to measure engine load. and flows EGR on LOAD. more load, more egr flow.

cheers,
http://www.fixkick.com
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#14
Dear Fixkick:
Thank you for your though reply,; however, I am now more confused!

Simple questions:
]1. Should there be vacuum in hose no. 27 at idle?
2. Should there be vacuum in it when revving the engine?
3. Is what I have described abnormal?
The engine backfires like hell! Everything else is set to spec. The TPS is 0 V at idle too.

Please tell me in layman terms whether the lack of vacuum is normal!

Cheers,
Zackman.

BTW, what should bethe value of the ignition advance (deg) at idle please?
Regards,
Zackman
[color=#800080][b]91 Sidekick JX, 8V, S. Carolina Car, 2 dr, 3 speed Auto Trani, Halifax, NS, Canada[/b][/color]
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#15
static advance with timing freeze jumper. inserted to DLC. next to battery.

the advance, is on the hood sticker, of cars, all usa cars.
look up and under see that sticker.
ill show my 91
the calif can be different from FED usa or fed canada.

http://www.fixkick.com/specs/Body-TAGS/h...age_4.html

i think most are 8degrees BTDC.
http://www.fixkick.com
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#16
So, if the Ignition adv should be -8 Deg BTDC? According to the Rhinoview, the car's ignition adv. is at +15 deg! How can it be?
I used the timing light to set it it at exactly -8 BTDC with the static timing bit. Moreover, I first thought the TDC might have been screwed up since I changed the timing belt. But, then I insured that the cylinder 1 is at TDC at the firing cycle (with valve lash lose), when I put the distributer on at 11 PM..

I understand that TDC is set when Cylinder 4 is at TDC, correct? Now the question is whether the TDC should be at the firing cycle of cylinder 4 (i.e., when the valve lash is lose?)
Could you please clarify this for me.

One last request; could please give me simple answers for the following questions that I asked in my last thread, but got no answer for (PLEASE!)
Simple questions:
]1. Should there be vacuum in hose no. 27 at idle?
2. Should there be vacuum in it when revving the engine?
3. Is what I have described abnormal?
The engine backfires like hell! Everything else is set to spec. The TPS is 0 V at idle too.

Please tell me in layman terms whether the lack of vacuum is normal!

Cheers,
Zackman.
[color=#800080][b]91 Sidekick JX, 8V, S. Carolina Car, 2 dr, 3 speed Auto Trani, Halifax, NS, Canada[/b][/color]
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#17
Hello
my guess is you timed the cam wrong, is compression over 150PSI on all cylinders, your altitude is 25meters. so must be. I BET NOT? and is check on my page in step 42
what cam cog do you have;?
this is all there is to do it.
http://www.fixkick.com/t-belt/8v-tbelt1w.jpg


there is no reason to look at valves.
at all for timing
if you use the correct parks, there is no way to get timing wrong, or get #4 work, at all, no way.

but ive no clue as to what cam cog you have
the 60a cog
or the 1990 , titty only cog.
they changed cogs some time in after July1st 1990. ive no clue as to when

so my web page covers both cog wheels.
got this
http://www.fixkick.com/t-belt/8v-cam-cog-close.jpg

or this (gen1 G16a engine cog , uses this wheel) note the lack of false marks !
http://www.fixkick.com/t-belt/sprocket1989-8v.jpg
http://www.fixkick.com
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#18
back to ported vacuum
here is the first youtube.
at this time mark
https://youtu.be/fQmO2H6Pbas?t=693

see how he tips in the TV , and the port is exposed, that is why its called ported vacuum

and Duane page
https://youtu.be/rXQeST68j9s?t=162
http://www.fixkick.com
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#19
let me say.
if you use the correct marks?
#4 will be firing, at TDC (by pure physical facts of the cam grind) the marks are in fact hard set in the factory for #4 firing,
only using false marks, can you get it wrong.
fact.
in fact , you can ignore #4 totally. (as the FSM BOOK DOES) in fact the FSM book fails to show false marks, at all.

in fact at the last step compression will exceed 150psi. on all cylinders. if not?, oops.
on old engines, its best to check compression at the drop of hat. (some are 27years old now, 8v)
as this tells you many things.
(if engine is viable? and if you should stop and fix the more pressing problems,,,, and not drive it.)

this engine with a stock cam and stock compression ratio, does 150psi cold and 170psi hot.
all do. at sealevel.

why pressing?
well , what if a valve lash is wrong, , it burns up the valve? best to find this at cranking time, spark defeated,. doing the test.
or its already burned up, and now you suck the valve , and have totally wrecked head.
pressing needs, all.
http://www.fixkick.com
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