Chevy & GMC Vans

Happy turkey day(s) to all of yaz.
Sac, CA owner here.

I’ve a couple Q’s for the experienced owners here.
Need some “point me in the right direction” assistance.

I’m at a crossroads.
Kid hit me hard in the pass side last year.
My ins adjuster totaled it out.
I had the ‘wrong’ kind of unins motorist coverage. (thanks for telling me, Progressive…)
I got $700 for my sore back…grrrrr……

No serious mechanical damage; cosmetic ‘blemishes’.
Pass door/slider still function, with the help of my trusty prybar.
Still drives just fine…until the last couple weeks.
I NEED this pup to work, until I get another one…which is upcoming.
I don’t want to sink buckets o’ $$$ into this one, but I need transpo.

94 Safari. Z. 2 WD, passenger. 182 K.
Bone stock.
Used for work. Daily driving to and from job sites. Lots of freeway miles.

3 + weeks ago, put a new water pump in.
Added orange Dexcool. (I know, I know…my bad…)
Dexcool ended up seriously sludging out.
Drained it, threw in some Prestone cleaner.
Still in progress on blowing out little chunks. (Drain, fill, drain, fill….)

The Dexcool/cleaner helped the water hose connector tubes under the AC unit spring a leak, which I have yet to find/repair.
I worked a temporary surgical bypass of the water hoses from the engine up to the heater in/out.
Had to remove a couple parts of the air intake tubes to get in there.
Didn’t hook those back up. (yet)
Air cleaner intake port now open in the engine compartment.
Van ran just fine for a while.

Then…
Coming on to the freeway, kicked it hard to get up to speed.
Heard a bit of a ‘clunk’ sound…
Got a nasty surge/hucklebuck going.
No passing juice at all anymore. Just won’t do it. Surge/hucklebuck.
It’ll still roll just fine on a pleasant application of the gas pedal on level surfaces.
Takes a while to pick up (I know, I know, it’s a heavy van…); will get up to the 70’s and ride, but does not accept a kick to pass the morons on the freeway.
Does NOT do hills well at ALL. Not enough juice to get up and over above 45-50 mph.
Not overheating. Temp gauge says ‘bout 160, pretty consistent.
Did about 200 miles yesterday; not QUITE ‘white knuckle’ but close.

Appears the second barrel of the carb has taken a powder/vacation.
‘Check engine’ light has come on under extended load (up hills), but does not come back on after it’s been shut off for short stops.

Ok, Safari/Astro gurus:
What are my options?

Pic and Pull trip for another TBI unit?
Do I HAVE to buy a code reader?
CAN the FI jets be cleaned, or do they have to be replaced? (Yikes!)

I’m looking for a (relatively) cheap, “quick” fix that will keep me comfortably/efficiently/safely on the road until some funds come in for another van.
(Yes, it will be a Safari…or Astro…I’m quite happy with these packages!)

Hope I haven’t bored you to death with my verbiage; it’s just how I type things out.

Thanks for your perusal, and more thanks for suggestions.

Happy turkey day to youz and yourz.

Pat

sounds more like a tranny problem like torque converter not kicking in or something like that . but don't quote me on that , there will be more knowledgeable guys posting so wait & see what they have to say .

Hi....i would see if you've got any fault codes in the computer. Because i'm to lazy to type a how to, i have coppied the info from astrosafari.co.uk (i'm a member) this saves you having to register..... (sorry to admins and mods if the info is already on this site, i couldn't find it )

so here goes, let us know what comes back...Johnny

This How -To is for owners with the 12 pin connector, if you have a 16 pin connector (pic 1) then this will need an OBD ll compliant scan tool to read any codes along with the relevant General Motors vehicle information software.



This information is generally classed as pre 96 model year.



Firstly the diagnostic connector has several names given in reference to it, the most common being:
ALDL (Assembly Line Diagnostic Link) or DLC (Data Link Connector) (pic 2 note the letters and their location)


The connector is located under the dash generally to the left of the steering column.



How it works:


All over and around the engine are situated sensors, "I still have not counted them all" These sensors are fed a current of electricity typically 3 - 5 volts, the Engine Control Module (ECM) recognises the value and presence of these voltage inputs, indeed it is these very currents that it translates into how well the engine is performing, adjusting the different elements constantly.


It (ECM) also notes when things go wrong ie the lack of a voltage or change in composition between 1 or more sensors. It stores these faults as a numbered code and assigns a code to a particular sensor that has faulty readings, as and when these faults or discrepancies occur the Service Engine Soon (SES) or Check Engine light on the dashboard lights up, either momentarily or in some instances permanently. (pic 3, electronic dash shown)



How to read the codes:


You will note in 'pic 2' the alphabetical order of the 12 ports of the DLC. Port 'A' top right, reading right to left then down and read left to right, finishing with 'M' below 'A' .For the purpose of this how -to we shall be dealing with ports 'A', 'B' and 'H'. In fact it would be quite rare to have all ports connected, (if lucky enough to have more connected there are terminals for fuel pump test, and air bag test.)



Port A is the ECM ground (earth).


Port B is the ECM diagnostic request (5 volt).


Port H is the Anti-lock brake data request.


To read engine/transmission codes, firstly, with the ignition off connect a piece of wire between port A and port B ( a straightened paper clip is ideal) once connected (pic4) turn on the ignition without the engine running and watch the in-dash SES light, it will begin to flash.


Firstly code 12 will flash, one flash ....pause...two flashes, this is an acknowlegement code indicating that the ECM is receiving a diagnostic request. Code 12 will cycle for 3 times then any other stored codes will flash again each cycling 3 times. Make a note of these numbers as they appear the range of numbers is between 13 and 82 not all being used. Once all if any stored codes have been cycled the code 12 flashes again and the whole sequence repeats. Turn off the ignition and remove the wire connector, once you are done.



How to Read codes from the ABS System:


If a problem occurs within the ABS system the in-dash ABS light will turn on. (pic 5)
With the ignition off , connect a wire between ports 'A' and 'H'. (pic 6) Turn on the ignition without the engine running. The ABS in -dash light will commence flashing, this time though there is no acknowlegement code, it will begin flashing up any stored codes straight away, again cycling each 3 times. When all codes are retieved it will cycle these numbers again. Once retrieved turn off the ignition and remove the jumper wire.



Clearing stored codes:


Once you have taken all of the codes you can erase the code memory from the ECM by either removing the battery terminals or removing the fuse ECM B from the fuse board for at least 30 seconds. Please note that the ignition switch must be turned off before removal of the power to the ECM, severe damage to the ECM can occur if this is not done.


To Clear ABS Memory:


Turn on the ignition, connect a jumper wire from port 'H' to 'A' for 2 seconds...remove the wire for 1 second....repeat this process, an indication of clearance success is when the ABS in-dash light lights and turns off. Turn off the ignition. To check for clearance try to read any ABS codes again.



In the event of either the SES light or ABS light,lighting up and codes not being retrieved, the code will automatically be lost should the problem not reoccur within 50 engine starts.



Codes retrieved either engine or ABS can be diagnosed by some of us on the site, it should also be noted that not always is the code represented the fault of the problem. merely an outlet.


If I have missed anything important out someone will no doubt correct me.


Happy code reading ("no should'nt say that, I hope you don't get any problems!")

Sounds like when you want to give it gas it ain't gettin' it. Could just be a dirty fuel filter.

Thanks for your responses!

Round 2:
Air intake snorkel hooked back up.
No change.
Vaccuum hoses all appear to be connected properly.
Service Engine light comes on after about 30 mins at 65 if I kick down to pass.
Light does not come back on after van turned off, unless similar conditions occur.
Light does not come on if I just meander smoothly and judiciously down the road…
while getting passed by almost everyone below the age of 70…
I do lots of freeway miles to get to job sites.
65 is the bare bones minimum to even begin to get there and back.
Try doing 50 on a freeway onramp at 6:15 A...scary...
75-80 have been my ‘normal’ operating speeds.

Runs well enough around town on city streets.
Still must apply gas pedal smoothly and carefully or I get the surges/choking.
Van will run up to 60-75 mph on flat surfaces. Slowly, but it’ll get there.
Kicking the gas hard to drop down a gear and pass at any speed is practically impossible.
Chokes out and stutters.
Almost as if the carb is choking on gas.
Appears primary carb barrel is functioning well; secondary barrel, not so much.

Won’t do freeway hills well at all.
Loses power to a crawl. (from 70 to 45-50 on the freeway…)
Gas mileage hasn’t suffered.
Getting 15.5-16.5, as it was getting prior to problems.

Indicators (to me) pointing to:
2nd barrel of the carb has issues.
Could be result of flamed out sensor or 3.

More questions:
What years and from what vehicles are carbs swappable onto my 94?
Pic and Pull is an option I’ll go to, if need be.
Not real into plunking down 3 Benjamins and change for 2 OEM injectors…

Will a $20 OBD reader (e-bay, et al…) work on telling me code faults?
If so, which of the Equus models listed work on my 94?
(3123 or 3173; both are listed to work on my ride)
OBD 1’s and readers appear to be slowly vanishing into history…

More work to do to fix it up.

In the mean time, I’ll be trundling down Hwy 80 with my fingers crossed and talking nice to my ride.

Thanks,
Pat

correct me if I'm wrong here guys, but I'm pretty sure a '94 is still obd 1:
if so, a paperclip bent into a hair pin shape and plugged into the A and B terminals, top row of the aldl, first and second sockets from the right side, will flash the error code on the ses light in the dash. As Johnny posted, first numbers flashed will be 1 and 2, one flash then two flashes. It will do this three times, then it will flash the error code numbers, first digit then second digit three times. Just based on what you've posted, my gut reaction is that your egr valve is sticking. It will throw a code, come unstuck later and the light will clear. The code is stored in the pcm even if the light goes out.
plug the paper clip jumper in, turn the key to the "on" position, do not start the engine, watch the ses light in the dash...and count. There's a pause between the number digits. If you have more than one error code stored, the first number digits will flash three times, then the next will flash three times. when it's done you'll get a 12 code flashed three times, a one....one two count.

also, that's not a carb on top of your intake, it's a throttle body injection unit

Thanks, k.
Yep, 94 is a 1.
McGyver reader! Me likeeeee!!!

This will narrow the repair field down.

Psssst...I know it's a TBI; I just like to 'think' it's a carb.
I can at least work on carbs without having to have a damn degree and a bottomless checkbook...

you need to get the code and see what it is. and a paper clip trick will give it to you just stick it into port a-b should be the only two pins side by side and read the code. give us that and this will help alot. im thinking a clogged up cat maybe.
Danny

Round 3:

Pulled the code.
12, 32, 12; 12, 32, 12
EGR down (?)
Damn! Another Benjamin and change…not yet, man , not yet…

Kept driving carefully.
Had hooked the snorkel back up, but hadn’t changed.
Day or so later, I just decide to try and kick it to get to fwy speed.
It worked!!!

Hasn’t been problematic since. No SES light, either!

Lesson learned:
“Old School” temp fixes don’t always work on newer auto systems.
A closed, computerized system is best run ‘closed’.
Too many sensors to tweak running it open.

Questions remain:
Can the EGR valve come back to life?
Can it be cleaned and re-used?
(And where IS the EGR valve, anyway?… )

What sensors should I track down, clean/spiff or replace?

Why does my heater take ages to come up to heat?
Didn’t do that prior to water pump swap and heater hose connector bypass.
Wrong hose routing??? Still plugged with gak from Dexcool?

Thanks again, folks.

Yes the egr can be cleaned. They do periodically get stuck due to carbon chunks jamming the pintle.
you can get a screened gasket to keep the carbon chunks out of it. here's one source: http://www.tomco-inc.com

Here are pics of Lockdoc's 93 Astro that had a real rough idling issue. The EGR was partially open due to a chunk of carbon.

Location on the engine looking right in from the front...



Here is the EGR...





And the chunk that was propping open the EGR pintle...