Check Engine Light on, need help with codes
#1
Check Engine Light on, need help with codes
Bought a 95 LT yesterday with the 4.3
Seemed fine, no lights on. Idled a bit rough, but it's a 95 with 165K, figured a tune up was in order.
Used almost 1/2 tank of gas to get home, about 65 miles or so.
Stopped at a friends house for a few, that was probably 15 miles.
Left his house, started down the road (like 2 minutes) and the CEL came on, started flashing. Get to town, pop the hood, check the oil. It was pretty low. Go to Auto Zone (don't hate, it was the closest place) and top it off.
Ran it to AZ today and had them pull the codes. Here's what I got
P0340
Cam Sensor Condition
Probable Cause
1-Cam Sensor Defective
2-Check Connector and wiring to sensor
3-Engine Mechanical condition-timing belt/chain out of time
P0305
Cylinder Misfire Detected-Cylinder #5
Probable Cause
1-Ignition system fault-spark plugs, ignition wires, coil
2-Vacuum Leak
3-Injector Fault
4-High or low fuel pressure
So I am not a motor head, but I know how to turn a wrench some. I know the Gm 3.8 motor very well. Don't know anything about the 4.3. I hear it's a good motor though.
SO, advice, tips? Best place to start? Any links to any good reading to bring me up to speed?
Advice on plugs, wires, etc... how do I change them. I peeked today, totally different than the 3.8 I am used to.
What about the Cam Sensor? What's the most common failure? The connector, the sensor it self? Oh, and where is it located on this motor?
Thanks in advance. If you need more info I'll answer what I can
Seemed fine, no lights on. Idled a bit rough, but it's a 95 with 165K, figured a tune up was in order.
Used almost 1/2 tank of gas to get home, about 65 miles or so.
Stopped at a friends house for a few, that was probably 15 miles.
Left his house, started down the road (like 2 minutes) and the CEL came on, started flashing. Get to town, pop the hood, check the oil. It was pretty low. Go to Auto Zone (don't hate, it was the closest place) and top it off.
Ran it to AZ today and had them pull the codes. Here's what I got
P0340
Cam Sensor Condition
Probable Cause
1-Cam Sensor Defective
2-Check Connector and wiring to sensor
3-Engine Mechanical condition-timing belt/chain out of time
P0305
Cylinder Misfire Detected-Cylinder #5
Probable Cause
1-Ignition system fault-spark plugs, ignition wires, coil
2-Vacuum Leak
3-Injector Fault
4-High or low fuel pressure
So I am not a motor head, but I know how to turn a wrench some. I know the Gm 3.8 motor very well. Don't know anything about the 4.3. I hear it's a good motor though.
SO, advice, tips? Best place to start? Any links to any good reading to bring me up to speed?
Advice on plugs, wires, etc... how do I change them. I peeked today, totally different than the 3.8 I am used to.
What about the Cam Sensor? What's the most common failure? The connector, the sensor it self? Oh, and where is it located on this motor?
Thanks in advance. If you need more info I'll answer what I can
#2
95 is kind of a "hodge podge" year for S & T body. 2 different fuel delivery systems, and 3 different computer controls were used. Your engine has what we call, "OBD1.5". (might be a good idea to add that info to your signature line). It's a transition system from OBDI to OBDII that controls your fuel delivery and emission systems. Not all scan tools can communicate with it. This engine is pretty fussy when it comes to tune up parts and fuel pumps. Plugs, cap, rotor and fuel pump need to be AC Delco. Plug wires need to be good quality, not some el cheapo store brand. If you don't know the history of these parts on this vehicle, probably be a good idea to replace them so you know where you stand. Next step is check fuel pressure and leakdown. The results will tell the condition of the fuel delivery system, including the fuel pump. The link below will help. It is actually written for 96 & newer, but the procedures are very similar for yours, and the specs are different. Post all 4 numbers and we will analyze them. https://blazerforum.com/forum/2nd-ge...eakdown-88305/
Any questions, just ask.
Any questions, just ask.
#3
THanks Captain.
There is paperwork in the glove dash of all plugs, wires and rotor all replaced about 5K miles ago. Not sure what brand was used. I'll look today and see what it says.
Good to know about using Delco parts.
I had a 95 Bonneville with the 3.8 that was 1.5 OBD. But AutoZone couldn't read that. They did read the Blazer though, so I thought maybe it must be 2. Maybe they just have a better scan tool now then they did years ago. It's probably been almost ten years since I had that Bonneville.
There is also paperwork about the fuel pump being replaced to, I forget when that was done. 'll check out those results and post back.
There is paperwork in the glove dash of all plugs, wires and rotor all replaced about 5K miles ago. Not sure what brand was used. I'll look today and see what it says.
Good to know about using Delco parts.
I had a 95 Bonneville with the 3.8 that was 1.5 OBD. But AutoZone couldn't read that. They did read the Blazer though, so I thought maybe it must be 2. Maybe they just have a better scan tool now then they did years ago. It's probably been almost ten years since I had that Bonneville.
There is also paperwork about the fuel pump being replaced to, I forget when that was done. 'll check out those results and post back.
#4
Read your post again. Pluges and wires I get. Again, total noob to this. What's a cap and rotor?
My 3.8 had three ignition coils, each with 2 posts. A plug wire went on one of the posts, and the other end to a plug.
My 3.8 had three ignition coils, each with 2 posts. A plug wire went on one of the posts, and the other end to a plug.
#5
Your old 3.8 had a distributorless ignition system.
These engines have a mechanically driven distributor that is located at the back of the motor behind the intake duct work, slightly off to the left when looking at the motor from the front of the vehicle. The cap & rotor are the pieces on top of the distributor that direct spark from the coil to the proper cylinders. Attached is a picture of a cap as well as an illustration of the distributor & engine for wire routing purposes. The rotor is located under the cap and is attached to the distributor shaft by two screws.
These engines have a mechanically driven distributor that is located at the back of the motor behind the intake duct work, slightly off to the left when looking at the motor from the front of the vehicle. The cap & rotor are the pieces on top of the distributor that direct spark from the coil to the proper cylinders. Attached is a picture of a cap as well as an illustration of the distributor & engine for wire routing purposes. The rotor is located under the cap and is attached to the distributor shaft by two screws.
#6
Excellent, thanks swart.
I'm starting to get the hang of this.
I'm trying to assemble and order parts ASAP and hoping to do this this weekend.
I am looking at RockAuto (hoping I am not breaking rules by naming a site) and don't know what to order.
I am looking at all Delco parts, but there are several to choose from for each category.
I see 2 choices for fuel Filters. There is less than $1 difference, so I don't care, just want to get the right one.
Fuel Filters
There's the ACDELCO Part # GF652F for $9.53
More Information for ACDELCO GF652F
Or
ACDELCO Part # GF652 for $9.80
More Information for ACDELCO GF652
I have 4 choices for wires
Spark Plug Wires
ACDELCO Part # 9716W for $27.99
More Information for ACDELCO 9716W
ACDELCO Part # 716W for $34.79
More Information for ACDELCO 716W
ACDELCO Part # 9726G for $35.79
More Information for ACDELCO 9726G
or
ACDELCO Part # 726G for $37.89
More Information for ACDELCO 726G
For the Cap I have 3 choices
Distributor Cap
ACDELCO Part # D314A for $9.14
More Information for ACDELCO D314A
ACDELCO Part # D580A for $11.44
More Information for ACDELCO D580A
or
ACDELCO Part # D328A for $25.79
More Information for ACDELCO D328A
And for distributor rotors I have 3.
Distributor Rotor
ACDELCO Part # D446 for $4.48
More Information for ACDELCO D446
ACDELCO Part # D557A for $4.96
More Information for ACDELCO D557A
or
ACDELCO Part # D465 for $8.33
More Information for ACDELCO D465
SO, which one of each do I need. Overall, the price difference won't be huge or prohibitive, I just want to get the right stuff.
I assume for plugs just get the regular Delco's?
Anything else anyone can think of that I should get?
I'm starting to get the hang of this.
I'm trying to assemble and order parts ASAP and hoping to do this this weekend.
I am looking at RockAuto (hoping I am not breaking rules by naming a site) and don't know what to order.
I am looking at all Delco parts, but there are several to choose from for each category.
I see 2 choices for fuel Filters. There is less than $1 difference, so I don't care, just want to get the right one.
Fuel Filters
There's the ACDELCO Part # GF652F for $9.53
More Information for ACDELCO GF652F
Or
ACDELCO Part # GF652 for $9.80
More Information for ACDELCO GF652
I have 4 choices for wires
Spark Plug Wires
ACDELCO Part # 9716W for $27.99
More Information for ACDELCO 9716W
ACDELCO Part # 716W for $34.79
More Information for ACDELCO 716W
ACDELCO Part # 9726G for $35.79
More Information for ACDELCO 9726G
or
ACDELCO Part # 726G for $37.89
More Information for ACDELCO 726G
For the Cap I have 3 choices
Distributor Cap
ACDELCO Part # D314A for $9.14
More Information for ACDELCO D314A
ACDELCO Part # D580A for $11.44
More Information for ACDELCO D580A
or
ACDELCO Part # D328A for $25.79
More Information for ACDELCO D328A
And for distributor rotors I have 3.
Distributor Rotor
ACDELCO Part # D446 for $4.48
More Information for ACDELCO D446
ACDELCO Part # D557A for $4.96
More Information for ACDELCO D557A
or
ACDELCO Part # D465 for $8.33
More Information for ACDELCO D465
SO, which one of each do I need. Overall, the price difference won't be huge or prohibitive, I just want to get the right stuff.
I assume for plugs just get the regular Delco's?
Anything else anyone can think of that I should get?
#7
Cap: ACDELCO Part # D328A for $25.79
Rotor: ACDELCO Part # D465 for $8.33
Wires: AC Delco part # 9746T or Autolite 96827
Fuel filter: ACDELCO Part # GF652 for $9.80
Spark plugs: AC Delco Part # 41-803
Rotor: ACDELCO Part # D465 for $8.33
Wires: AC Delco part # 9746T or Autolite 96827
Fuel filter: ACDELCO Part # GF652 for $9.80
Spark plugs: AC Delco Part # 41-803
#9
They apply to 1995 with OBD1.5 only. Early 95 and older use a different cap, rotor & wires. Newer use the same cap, rotor and wires, but different plugs. As mentioned in post #2, 95 was a hodge podge year, one of the reasons GM did not produce the Bravada that year.
Last edited by Captain Hook; 03-09-2015 at 05:35 PM.