Need advice on 2002 Chevy Astro AWD repairs - IT RUNS!

Peter Person

Peter Person

501 Club
In the midst of replacing the lower intake manifold gaskets on our 2002 Chevrolet AWD Astro. 180,000 miles on the van.

Finally bit the bullet after we had two episodes of the van not starting recently, both after it had sat through some very cold damp weather in the garage. Two days after the 2/8 Blizzard we had rain-fog-warm air that caused water to condense on everything in the garage. Van would not start. Waited till the next weekend and took the doghouse off, looked the distributor over, checked for spark, made sure everything was connected. We got the van to start however it was really rough for a few minutes. Van ran fine for two weeks and the same thing happened again only this time, no go. If it’s not going to run might as well tear it down.

Additional symptoms/concerns; (Failed Connecticut emissions test in November)
• PO304: Cylinder 4 Mis-fire. Under certain conditions shortly after starting the van it would “buck” going up an incline. Step on the gas and it would stop. Once fully warmed up the “bucking” would go away except on a downhill off-the-gas run. The service engine light would flash on/off during the coasting downhill. The emissions testing garage thought the intake manifold gasket problem could be the cause of the misfire code.
Also - PO440: Evaporative Emission System

Recent history – too much money into the van to just wholesale/scrap it.
• Intake manifold gaskets have been leaking for close to two years, just enough to smell antifreeze after exiting the van and requiring a refill of the reservoir every couple of months. Within the last 6 mos or so there has also been a gasoline smell after shut down. We have been using a quart of oil every 1500 miles since 100k – no puddles on the garage floor and no real blue smoke on start up. Still lots of power so compression must still be OK.
• (4) Tires May 2012.
• ‘Y’ Pipe & Cats Jan. 2012.
• Fuel Pump Nov. 2011.
• Plugs, Wires, Rotor & Cap, PCV Valve Nov. 2011.
• Front Wheel Bearings and Rebuild Front Diff. March 2011.
• Front Rotors & Pads
• Alternator Feb. 2011.

Had help from Erik and Aron on Saturday to take things apart.

I ordered a bunch of parts from Rock Auto Sunday afternoon and they shipped Monday afternoon but am wondering what else we should replace while we have "the hood off".
On order;
• Upper & Lower Radiator Hoses as well as the small By-Pass Hose
• Thermostat
• Fel-Pro PermaDry Plus Gasket Kit
• Distributor Mounting Gasket
• Plugs, Distributor Cap & Rotor
• PCV Valve
• Radiator Cap (original is really corroded)

The intake manifold gaskets were definitely leaking near the rear of the engine. Looking at the engine block and the manifold it appears the rear coolant passages on the block dead-end at the intake manifold. Lots of crud caked in the engine block here and this is where the gaskets were in bad shape. Not a lot of damage to the castings though.
After removing the plastic intake cover exposing the “Spider” there is a lot of oily residue on everything inside.

While it’s opened up should I consider replacing;
• Spider – Rock Auto has the GB Remanufactured SCPI Fuel Injector Assembly for $159 plus $85 Core charge
• Water Pump
• ??

Sorry for the long post – but thanks for any advice.
Peter
 
Peter, I know what you are going through having been the owner of a 200 Oldsmobile Silhouette. We loved the van but it was a money pit. We replaced the head gaskets (thanks to Dex Cool http://www.consumeraffairs.com/news04/2 ... xcool.html) but problems didn't stop there. Before getting rid of the van we had rebuilt the tranny, replaced the rack & pinion and a host of regular maintenance items. I kept thinking the same thing as you, "I've got to much money in it to get rid of it" and kept thinking that the last repair would be the last repair for a while.

Each time something else would happen, I'd weigh the cost of the repair against the cost of car payments and usually the cost of the repair would be equal to just a few car payments. Seemed cheaper to keep her, if you what I mean. The last straw was when the head gasket failed again. I put an ad on Craigslist and sold it for $1500. There comes a time when it makes sense to cut your losses and I had reached that limit. One other thing that kept me repairing the van as much as I did was I loved the van. If drove good and was decent on fuel. But in the end I know I made the correct choice in moving on to another vehicle. It may just be me but, I've never had a Ford that gave me much problem. My wife is now driving an '06 Ford Freestar and so far, so good.
thumbup.gif
 
your gas smell sounds like rotted fuel lines. i had a strong gas smell on my yukon and it was the fuel pump lines at the pump. you should have the fuel system smoke tested. its a machine that hooks up to the fuel system and pressurizes it and if there is a leak it will show up as smoke. mine was billowing out at the fuel pump.
 
Rob,
Would the fuel lines rot out that soon after the fuel pump was replaced?

Ricky,
You pegged the situation perfectly. Wife loves the van, it seats 8, though we won't need that capacity much longer, and I need to get something that gives 30mpg for my commuter vehicle. The Silverado gets 16-17mpg but $100 per week for gas is adding up. At the very least I need to get the van running so it can be sold.

Peter
 
Peter Person":2smp5g15 said:
At the very least I need to get the van running so it can be sold. Peter
Click to expand...

That's what I was thinking when the head gasket failed the second time but after considering the cost of the repair and the retail selling price of the older van, I opted to to accurately represent the van and sell it as a project for someone else.

WARNING: Cheap vehicles advertised on Craigslist seems to bring out all the local jerks.
banghead.gif
 
Peter, The parts you have on order are definitly a good start towards repairing the van.
These Vortec engines a very prone to leak at the lower intake gaskets, The red coolant IMHO is the main problem,even though GM will deny it. It will also cause your misfire code. Chances are good that you will solve most of your problems with the intake gaskets. Be sure to torque to specs as these gaskets are plastic.
I would hod off relpacing the injector spider at this time as it can be accessed via the upper manifold
PO440 is a gross evap leak and mst likly is no related,could simply be your gas cap.
If you have more questions shoot me a PM and I will give you my ph #.
Bll
 
You got a lot of good advice here..

I only worked on Astro’s when they were in warranty….when they were out of warranty the customer didn't return to the dealer; they took them to a real shop so they would get their vehicle repaired correctly...just kidding.

Some info

The no start under moist conditions was a big problem with the 4.3 L Astro’s. What I was doing for a fix was spraying a good ignition sealer inside the distributor cab, let dry, clean the ignition sealer off the electrode point(s) install the distributor cab and spray the ignition sealer outside the cap and try to water proof. GM said the problem was the buildup of condensation inside the distributor cap under certain conditions and made vented the distributor cab to replace the OEM cap if the customer complained of no start under moist conditions.

If I remember G.M. had a recall on the 4.3 L Astro of rerouting a wire harness between the coil and distributor it contacted a bracket near the distributor which caused a miss-fire.

Occasional problem(s) ...failure of the Front Wheel Speed sensors (ABS)

Common problems on this vehicle are failures of the Crankshaft Position Sensor, Fuel Pump, Fuel Injectors, Fuel Pressure Regulator, Distributor Cap, AWD and intake manifold gaskets leaking coolant.

SES light flashing on and off is a warning for the Catalytic Converter. Because of the engine misfire you may be hurting the Catalytic Converter.

After removing the plastic intake cover exposing the “Spider” there is a lot of oily residue on everything inside. - Normal

Spider – Rock Auto has the GB Remanufactured SCPI Fuel Injector Assembly for $159 plus $85 Core charge… SCPI was always a big problem…I would replace…

Water Pump- Check the shaft play... if its tight and you're not going to keep the van that long...maybe take the gamble... but if your luck is like mine....

Sometimes from the symptoms you have described the ECM (computer) is counting misfires at higher rpm due to some play in the timing chain. This can be repaired (sometimes) by doing the crankshaft position variation relearn. This has to done with a scan tool.

If you decide to do the water Pump with that amount of miles you should do the engine timing chain.

??...Accessory drive belt (Fan belt)…. anything obvious... ya…I know…

Very important…

Gas smell may be the Fuel Pressure Regulator; you can see if it’s leaking…big problem with the Fuel Pressure Regulator’s leaking

Clean the intake Plenum, and check very careful for cracks and surface straightness.

DTC PO440 is an evaporative system leak and you need to find where that is…In a shop a pressurized non explosive gas with colored dye is used to find a leak. Check visually first….fuel cap seal could be the issue.

Clean the ports where the poppet valve(s) (fuel injectors) go into the intake manifold really good.

Follow instruction from the service manual closely during reassembly.

You’re lucky you can do this yourself; I can only guess the cost if you had to pay a shop to do this.

I hope this helps somewhat.

P.S…..New ones break too, I have a late 2012 Chevy 3500 HD that’s having second time issues. Lucky it’s under factory warranty and being and retired Chevy Tech I understand what the Tech is going through trying fix the truck…second time around for the same thing…I’m beginning to wonder if it’s a engineering problem. God knows how many times I had that issue when I was working…. I’m so thankful those days are over with….a customer screaming at me why I can’t fix their car that just cost them $30,000 knowing it’s an engineering problem….
 
You didn't mention which engine you have, but most of these were built with the 4.3L engine.
I have had 3 vehicles with this engine and each one ran well over 200K miles each.
Your misfire is likely due to a good tuneup needed but also could indicate a coolant leak (into the cylinder).
Changing the distributor cap and rotor, wires, and spark plugs should eliminate most of the tuneup questions. Note: Using GM Parts on these engines really helps! My vehicles did not run well when I used Autozone or O'Reilley tuneup components.

If the issue does not go away after the tune-up, then you are looking at solving the coolant consumption. Jack also mentioned the crankshaft position sensor. This also could cause the issue if there were a poor connection.

Word to the wise... As soon as you get it running well, sell it. At 200K miles, this vehicle is probably nearing its end of servicable life. The oil and coolant consumption is the indicator.
 
outdoors4evr":3vrmiv1y said:
Note: Using GM Parts on these engines really helps! My vehicles did not run well when I used Autozone or O'Reilley tuneup components.
Click to expand...
Local car dealerships get some of their parts from the auto parts stores.
 
It RUNS!
We had it all back together Sunday night but "while we had the hood off", i.e. the front wheels to get to the spark plugs, we noticed the brake pads were pretty gone, so we picked up some pads and went to put them on and discovered one of the caliper bolts was in bad shape. Fortunately the threaded hole in the caliper was OK. Advance Auto did not have a bolt in stock so they ordered it Monday night and it arrived Tuesday morning. Aron finished up the brakes today. We tried to start it Monday night after we finished the oil change, but the battery was dead. Put it on the Harbor Freight cheapo-junk charger overnight and gave it a go Tuesday morning - nuthin. Brought the battery to 4H Tuesday night and put it on the advisors industrial charger for 2 hours. It took a charge but drained to '0' when load tested....so off to Tractor Supply at lunch today to pick up a battery.
Got home tonight, put the battery in and the engine fired right off. After a rough 5 minutes it started to smooth out. Took it for a run and everything seemed OK. One oddity is the distributor makes a racket, same as it did before we replaced the cap & rotor. It sounds like the tab on the rotor is hitting the contacts in the cap. Once the dog-house is back on the sound is barely noticeable from the front with the hood open. Any ideas why the noise?

One last shake-down run tomorrow to work - 35 miles each way - before turning it back over to my wife.

Then it's on to the Silverado - discovered the front wheel bearings are toast. Ordered and shipped today, hope to have by Friday.

Thanks for all the advice!

Peter
 
You should not hear noise like that …Is the noise at the cap area or does it sound deeper?

Tips
Remove the cap and inspect the inside of it to see if anything is making contact, make sure the rotor is seated correctly…make sure the cap is seated correctly….wiggle the distributor shaft to see if the bushings are tight….check the distributor shaft to see if it bent.
 
I hope your Silverado wheel bearings come out easier than mine did! When I bought the truck, last spring, the right front had just been replaced but in November the left front went out. Removing the fasteners & such was pretty straight forward but the bearing was rusted very tight in the knuckle. I worked and worked to get it out. I don't remember what finally worked but I got it. Re-assembly took only a few minutes. Maybe some of the other techs here will offer some tips. I've changed quite a few bearing, of this style, but never encountered one quite this tough.
 
Rob in NH":3bb3skzd said:
pete, did you find out where the gas smell was coming from?
Click to expand...

Rob,
I did not find where the gas smell was coming from. The O-rings in the fuel line connection at the rear of the engine were pretty shot and replaced with new ones included in the Fel-Pro gasket kit.
No apparent problems on the 35 mile trip to work this morning.

JackF":3bb3skzd said:
You should not hear noise like that …Is the noise at the cap area or does it sound deeper?

Tips
Remove the cap and inspect the inside of it to see if anything is making contact, make sure the rotor is seated correctly…make sure the cap is seated correctly….wiggle the distributor shaft to see if the bushings are tight….check the distributor shaft to see if it bent.
Click to expand...

Jack,
Noise is right at the cap. Rotor is seated, cap is seated - screws are tight. The distributo shaft has a plastic sheath from the gear teeth up to the cap.
Van runs great - no misses - plenty of power.

Peter
 
Peter,
You’ll hear some noise from the spark arc and that’s it. If more than normal I would do some checking…pretty cold out there to be in the shoe leather mode…

Chevy truck front wheel bearings...
This is the way I did it when I couldn’t remove them.....The wheel bearing really gets rusted into the spindles. Ignore the attitude of the man in the video; he’s really not that bad in real life….he needs to work on a couple of Fords to adjust his altitude.
http://www.youtube.com/watch?v=8Ly3pC8tzDc
 
Eugene":2prj6uhe said:
outdoors4evr":2prj6uhe said:
Note: Using GM Parts on these engines really helps! My vehicles did not run well when I used Autozone or O'Reilley tuneup components.
Click to expand...
Local car dealerships get some of their parts from the auto parts stores.
Click to expand...

Some people on here are WAY TOO CRITICAL! Sounds like you need a :||):
I am agreeing with you. Using the OEM components usually works out the best - regardless of what is supplied at dealers. That goes for car dealers & tractor dealers.

Peter, I am very glad you got it back running again. It's nice to hear them purring rather than coughing.
 
:applause: Glad to hear your efforts paid off on your van.
I have used the method that Jack sent you via youtube on the Silverado and it works well .
Bill
 
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