Sick 93 SSEI
#11
Mine'* an Actron. $140 from autozone including the gm cartridge. OBD1 only. I'd have liked an obd1/ AND 2 capable tool, but they're more than twice as much. I bought the cheapest scanner I could find that would tell me everything I needed to know.
#12
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From: Muskogee, Ok
Trip to the shop
I went to Autozone to buy an obd 1 scantool and the only kind they had did the same as the jumper and count the flashes. I went to another parts store and all they stocked was the obd II scantool. So I took the car to a shop that a friend had recommended and asked them if they could pull the other codes that you cannot get using the jumper method. They said $45.00 and they would hook it up, I said ok. Well 2 hours later the tech came back with a print out off of a Sun Diagnostic Machine and the diagnosis was air/fuel mixture too rich at idle and cruse speed. The machines recommendation was to check and inspect fuel pump, fuel pressure regulator and injectors, air induction system. Also check engine sensor & cat converter, if ok check all electrical and vacuum connectors, ECM? I told them I suspected a bad MAF at first so they checked that also the tech said that the wavelength was ok but he did notice that the RPM increased about 200 RPM once will he was tapping on the MAF (possible bad MAF)
They checked the fuel pressure with their gauge and it was 41 psi key on engine off and 35 psi engine on at idle (on the low side). When I got home I hooked up my fuel pressure gauge and wire tied it to a wiper arm so I could road test fuel pressure. The results were 35 psi at idle but when I would get on it the pressure would drop to 20 to 25 psi before it would go up to 40 psi then go back to 35psi.I thought fuel pressure was suppose to increase as vacuum decreased. I am thinking regulator or fuel pump at this point.
I called another shop and asked if they could pull the other codes that the pcm had stored other than the flash codes using the jumper method, and he said there are not any (I guess us Okies are a little slow at this sort of thing) .I don’t know what to do short of taking it to a GM dealer and paying big bucks to fix the thing.
The b/* meter went off when the first shop recommended I get a Motor Vac Treatment (that’* where they suck money out of you wallet)
They checked the fuel pressure with their gauge and it was 41 psi key on engine off and 35 psi engine on at idle (on the low side). When I got home I hooked up my fuel pressure gauge and wire tied it to a wiper arm so I could road test fuel pressure. The results were 35 psi at idle but when I would get on it the pressure would drop to 20 to 25 psi before it would go up to 40 psi then go back to 35psi.I thought fuel pressure was suppose to increase as vacuum decreased. I am thinking regulator or fuel pump at this point.
I called another shop and asked if they could pull the other codes that the pcm had stored other than the flash codes using the jumper method, and he said there are not any (I guess us Okies are a little slow at this sort of thing) .I don’t know what to do short of taking it to a GM dealer and paying big bucks to fix the thing.
The b/* meter went off when the first shop recommended I get a Motor Vac Treatment (that’* where they suck money out of you wallet)
#13
Re: Sick 93 SSEI
Originally Posted by Okie From Muskogee
My 93 Pontiac 3.8 lt. Supercharged Bonneville has developed a bog on acceleration. Sometimes when I accelerate from a stop or at speed the boost goes up but the engine bogs or hesitates until I let off the gas. This happens at random, 3, 4, 5 times a day. Some days not at all the car runs fine otherwise except it has NO POWER. I have changed the plugs, plug wires, fuel filter, air filter and added a can of Berrymans to the gas. The computer has no stored codes and no check engine lights are on.
If you've got a supercharger nosedrive leak, that'* a different matter altogether. I think your convertor is toast anyway.
#14
Originally Posted by jr's3800
I'd agree that the CAT could be bad... But there is more evidence pointing the other direction...
In fact I kind of doubt the supercharger is really boosting all that much, if at all, but the excess backpressure is going from intake vacuum to intake positive pressure, which of course pushes the boost gauge into the boost zone.
Anyhow, I would just test the intake vacuum readings to check for normal backpressure. I bet a problem is going to turn up there.
#15
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From: Muskogee, Ok
Vacuum Readings
Here are the vacuum readings off of the Sun Machine
High Cruise 21.1 , Low Criuse 21.0 and Idle 19.0 and all readings were steady.The Sun machine also reported idle speed at 813 rpm (spec max 700)with CO at 1.03 (max 100)at idle
High cruise CO 3.72 (Max 100) and low criuse CO 3.74 (max 100) Rich Mixture.
Compression ,power balance and spark all ok.
Thanks Keith
High Cruise 21.1 , Low Criuse 21.0 and Idle 19.0 and all readings were steady.The Sun machine also reported idle speed at 813 rpm (spec max 700)with CO at 1.03 (max 100)at idle
High cruise CO 3.72 (Max 100) and low criuse CO 3.74 (max 100) Rich Mixture.
Compression ,power balance and spark all ok.
Thanks Keith
#16
I'm not familiar with the stock vacuum specs. Somebody else is going to have to grab that. You ARE running rich though. This could be as simple as a MAF. Still damn hard to tell. I'd love to see some realtime scan data and compare it to my car (even with my chip, we should be close).
#17
Originally Posted by jr's3800
I'm going to ask for one thing here... Next time quote everything I said...
Originally Posted by jr's3800
I agreed that the cat could possibly be bad, but he has also had low fuel pressue readings as well... 20-30 psi is too low for any of these 3800 engines.. This will cause the engine to bogg and or hesitate under any acceleration.. It should stay around 40 PSI the majority of the time... up and down a little...
Originally Posted by jr's3800
I'll be glad when he finds the cause for the problem so he can get it corrected and be able to drive his car once again..
#18
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From: Muskogee, Ok
Hey Guys I Didn't Mean To Start A War
I took some of all of your advice. I changed out the fuel pump last night. And that helped with the low fuel pressure, and improved the performance somewhat. I got the cat converter changed this morning ,THE POWER IS BACK. I think between the fuel pump heading south and the converter plugging up, it has had me banging my head against my computer monitor for the past week. Now that the Bonne is running good my wife wants her car back.
Thanks Guys for all your help.
PS Now I have to replace the */C coupling, nosepiece seal and maybe the bearings. Can you pull the nosepiece without pulling the */C? Or would it be best to pull the whole */C?
Thanks Guys for all your help.
PS Now I have to replace the */C coupling, nosepiece seal and maybe the bearings. Can you pull the nosepiece without pulling the */C? Or would it be best to pull the whole */C?
#19
The nose can be removed while the supercharger is mounted on the engine...but I found that it'* easier to remove the supercharger to work on it anyway. If you just want to remove the nose, you have to remove the supercharger/alternator bracket, and that'* not easy.
By the way, how long did it take you to replace the fuel pump, and how hard was it?
By the way, how long did it take you to replace the fuel pump, and how hard was it?
#20
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From: Muskogee, Ok
Fuel Pump Change
It wasn't too hard. The hardest part was getting my big hands up in there to unhook the fuel and electrical connectors.Try and run as much fuel out as possible before you start. I took me about 3 hrs to change the pump.
This is a quote taken from another post
"Next the trick I learned. First the entire car needs to be lifted. I did this by using ramps on the front and jackstands at the rear. Both rear tires should be removed for easier access to the fittings and clamps. Buy a fuel line tool from the parts store, mine costs $3.99 at Auto Zone and was worth every penny. Buy new fuel line clips while at the parts store, again $3.99. Use a floor jack to slowly lower the tank and to put it back in. There is a pesky wire that goes to the ABS sensor on the driver side, undo the connector on the passenger side and remove the clip holding the wire tight, this will give enough slack in the wire so it doesn’t snag on the tank when its going back in. And remove the two hangers on the muffler so the exhaust hangs down several inches, just rest the muffler on a bucket. This allows room for the tank to clear the exhaust.Emptying the tank is the tricky part. I only saw one way to do it and that is to remove the vent pipe on the filler and siphon from there. The total job was about 2.5 hours."
This is a quote taken from another post
"Next the trick I learned. First the entire car needs to be lifted. I did this by using ramps on the front and jackstands at the rear. Both rear tires should be removed for easier access to the fittings and clamps. Buy a fuel line tool from the parts store, mine costs $3.99 at Auto Zone and was worth every penny. Buy new fuel line clips while at the parts store, again $3.99. Use a floor jack to slowly lower the tank and to put it back in. There is a pesky wire that goes to the ABS sensor on the driver side, undo the connector on the passenger side and remove the clip holding the wire tight, this will give enough slack in the wire so it doesn’t snag on the tank when its going back in. And remove the two hangers on the muffler so the exhaust hangs down several inches, just rest the muffler on a bucket. This allows room for the tank to clear the exhaust.Emptying the tank is the tricky part. I only saw one way to do it and that is to remove the vent pipe on the filler and siphon from there. The total job was about 2.5 hours."