3800 series II problems!!

[DKap7]

Running okay for now...




I have a 97 grand prix gt... It was randomly stalling on me and I ended up replacing the cam shaft position sensor.. It seemed to fix the problem.. Then One day, I got gas and went to star the car and it stalled immediately, the only way I could get it to stay running was to hold the gas down.

I let it sit for a while and then it fired right up and drove normal, I got it back home and when I parked it stalled and the same problem again...

I drove it a few places without any problems at all, it ran fine... Then I went to move it and it started but was loping really hard and there was a ton of smoke light in color coming out of the exhaust... I tried driving it and could put the gas to the floor and it would sputter and barely go.

So I heard that the IAC valve (intake air control valve) goes bad and could cause the problems. So I put a brand new one in and it seemed to idle really smooth and run a lot better....

Then I went to the store, came back out around 20 mins later and I had the same problems it was barely running and sputtering and loping with a lot of heavy gas fumes.. I started driving and after about 1000ft it seemed to clear up and all the power came back and it was driving fine again...

Sorry for the long post just wanted to give as much info as to what was going on as possible.... What should I try next?

[KUGS]

Pull the EGR valve off and makem sure there are no chunks of carbon holding the valve off the seat.

[89silverado2500]

tps?

[DKap7]

Will look into the EGR valve, and I just bought a TPS and put it in, but I snapped a vacuum line connector while doing so. So I need to get the fixed and see how it runs. Thanks for the replys!!!

[DKap7]

Tps changed and I removed the EGR and cleaned it and put a new gasket on it... So I drive about 10 miles and go into the store about 5 mins later come out and start it up and it dies right away... I had to hold the gas down slightly to keep it running again.. I started driving down the road and it was sputtering real hard and then all of a sudden it cleared up again like usual and was fine the rest of the time... Stopped again got back in the car and it fired up no problems at all.. And its been fine on the last few times ive started it.. Just once in a while it seems it just wants to act up when I try to start it... WTF...???

Someone told me it might have something to do with the temperature control sensor?? Said that it might be sending incorrect temperature readings and causing not enough or too much fuel to be sent... Any comments on that???

[eddieY87]

Tps changed and I removed the EGR and cleaned it and put a new gasket on it... So I drive about 10 miles and go into the store about 5 mins later come out and start it up and it dies right away... I had to hold the gas down slightly to keep it running again.. I started driving down the road and it was sputtering real hard and then all of a sudden it cleared up again like usual and was fine the rest of the time... Stopped again got back in the car and it fired up no problems at all.. And its been fine on the last few times ive started it.. Just once in a while it seems it just wants to act up when I try to start it... WTF...???

Someone told me it might have something to do with the temperature control sensor?? Said that it might be sending incorrect temperature readings and causing not enough or too much fuel to be sent... Any comments on that???

regarding the temperature sensor... I had to replace the coolant temp sensor on my firebird (same engine as you) and the symptoms were nothing like you described. So my guess would be its not that, but I could be wrong.

[DKap7]

Ah okay. I was just rhrowing that out there because the guy mentioned it... The damn problem is so random, I drove the car around most the day today and didnt not have any problems...

[DKap7]

Okay so it randomly decided it did not wan to start out of the blue, and the next day it started up lol.... I was told it could be a bad coil pack... I can replace all 3 for pretty cheap, not sure if that would help though...

[DKap7]

I pulled all 3 coil packs to test the resistance with my ohm meter... They all checked out okay, except the 1, 4 coilpack had a lot of corrosion on the top contacts that the plugs plug onto... And it was pretty hard to geta solid reading from them due to that... I cleaned them up really well and the others too reinstalled them and havnt had the problem yet... So well see if that was it or not... I guess time will tell....

[89silverado2500]

id say make sure you put dielectric grease on ever connection. the stuff can be messy but it helps keep a solid connection and prevents corrosion. msg me if you have any questions I know these 3800 motors pretty well

[eddieY87]

I might message you in the future with 3800 questions, got one in my bird.

[89silverado2500]

hey sounds good to me man. I used to be in a grand prix club here in michigan but with college fulltime, working in a bodyshop fulltime, and having a weekend job I kind of widdled away from that, and also I bought a 89 silverado (project truck). But I have my 05 grand prix gtp for sale at the moment.

[DKap7]

Good idea, I will pick up some dielectric grease and put it on... I sure hope this solved my problem lol, im getting tired of replacing things blindly!

[tylerz281500]

this happened to my freinds car recently. does it idle high when first started and then drop down, because its suppose to . if it doesn **** usually idle air control

[DKap7]

this happened to my freinds car recently. does it idle high when first started and then drop down, because its suppose to . if it doesn **** usually idle air control

MIne was just starting then instantly dying out. I had to hold the gas down to keep it running, then it would run really rough.. After I drove it about 500ft or so it would clear up and be fine... Then one day it wouldnt start at all it wanted to and acted like it was going to but wouldnt.. I have not had the problem since, but time will tell...

[DKap7]

OMFG!!!!! Its back same old ****! It doesnt want to start again.... WTF!!!!! I guess im going to drop it off at a mechanic I know and let him have at it and see what he comes up with, im so pissed off at it!!!!!!!!

[tylerz281500]

first go to autozone, or advanced, ahve them read it for you... around here they will read your codes if your car is obdII for free. then go from there, see what codes it brings up, and then test those. itll help diagnose it

[89silverado2500]

DKap7- might to be too much to ask but can you get a video of what its doing? and have you checked your oil level or your fuel pressure? reason I ask oil level is because I have had a vehicle in the past that if the oil would go just a lil below a certain mark that there was considered not enough oil, and it did exactly what yours is doing. of that it will only stay running if you hold the gas down. because from what I heard why it would do that is because if not holding the gas down the computer reads that its not building pressure so it shuts it down to prevent further damage. and while you hold the gas down your giving it fuel keeping oil pressure alive pretty much. but check if you oil is a little low and if it needs a quart or two top it off. also have you checked your fuel filter lately? how many miles are on the car?

[DKap7]

I took a vid of me trying to start it. Ill see if i still have it. And I just got the oil changed a week ago but ill still check it. The fuel filter is newer. I actually put a pin hole leak in the gas line because they were so rusty when I did the filter. I had a guy fix it for me though.

[tmack6]

Have you checked in to the MAF sensor?

[Badass69]

My 96 Caprice's LT1 had your described symptoms and they were completely random. Sometimes I could drive for an hour or more with no problem and then it was start stumbling, trying to stall and wouldn't stay running without my foot on the throttle. In my instance it was my MAF and it never threw a code throughout all of it's stupidity. I put one on off of a junkyard LT1 and voila, problem gone.

The CTS will usually cause startability problems moreso than stalling. It's possible but I am guessing not. I hate throwing parts at cars but if you can try an MAF it may be worth a look.

[tmack6]

My 96 Caprice's LT1 had your described symptoms and they were completely random. Sometimes I could drive for an hour or more with no problem and then it was start stumbling, trying to stall and wouldn't stay running without my foot on the throttle. In my instance it was my MAF and it never threw a code throughout all of it's stupidity. I put one on off of a junkyard LT1 and voila, problem gone.

The CTS will usually cause startability problems moreso than stalling. It's possible but I am guessing not. I hate throwing parts at cars but if you can try an MAF it may be worth a look.


X2 on that. I have a Buick T Type Turbo with the 87 LC2 (GN engine) and its related to the 3800 series engine. The MAF sensors in these cars can cause what he is describing. I went thru 3 MAF sensors before I converted to a the LT1 MAF and Translator. The MAF in these cars measures incoming air volume and lets the computer know how much fuel to inject throughout various points in the rpm band. If its dirty or bad the car will run like ish and not idle right, pop, sputter, and sometimes die. If you want to find out if the MAF is bad do the following.

Start engine (if you can)
With a screwdriver handle or something similar lightly tap the MAF sensor.
If you notice a dip or change of RPM the MAF sensor is bad.

Or

Remove MAF sensor
Look at the conditon of the circuitry inside the sensor.
If its convered in oil and dirt chances are the MAF needs to be cleaned with MAF sensor cleaner only or replaced.

[DKap7]

I pulled the maf before and cleaned it with maf cleaner. I will see if it will start and try tapping it.

[DKap7]

All right! So I got it to start and it was loping really hard and there were a ton of exhaust fumes pouring out... I got out and tapped the MAF, and BOOM idled up high and cleared out, I tapped a few more times and I got it to dip for a second then it idled back okay I managed to crack the top of the MAF lol... So I just bought another one and threw it in, so far so good... As of now I shall chalk it up as the MAF... Thanks for the help everybody!!! :FSCrules:

[tmack6]

:head: Tight!!!! Make sure you keep your receipt if you got the MAF from A-zone because I went thru 3 of them within a year. On the Turbo Buick Forums many members have had A-Zone Mafs take dumps on them. I have a powerlogger data logging system in my car and I literally watched the maf read from 0 Grams per second to 160+ grams per second while at idle. Then while I was at WOT it would only read 125 grams per second which made my car run dangerously lean at a very low boost setting of about 14 psi. I was like wtf is going on so I switched it out at the zone for another. The replacement had the exact same symptoms so I replaced it again. 8 months later that one went out to. Needless to say I got my money back and ungraded to the LT1 MAF and translator. Problem solved.

[DKap7]

I got it from advanced, I had a 30 dollar off coupon I used online. Its a reman, but has a limited lifetime warranty. I really hope it stays running right this time... I think the car has some sort of electrical problem, because when the low gas chime goes of it cuts out the radio and the info lights(MPG/DTE etc.. screen) cut out and back on also when I open the door the radio will cut out and back on its weird... Also I changed out the blower motor resistor and the old one was melted partially... The new one went out in a few months, I haven't swapped it yet, but I suspect I have some kind of electrical problem...

[DKap7]

SO not sure if its the MAF or what but now at idle its dipping really low like its going to stall then comes back up to normal.. It did actual stall out completely when I put it in park, but it started right back up no problem... It will be idling fine then drop way down to almost 0 then sputter back up and even out...

[tmack6]

Have you checked all the engine grounds, fusible link down by the starter, or loose/corroded alternator wire? If all those are okay...pull that MAF off and take it right back. I wish you had some type of data logger because you could see if the MAF was acting up or not. Those reman units are notorious for being outta wack right out of the box.

[DKap7]

Is there any website or anything that can give me a reference as to where the engine grounds are and all the stuff? Im not real sure where to look for everything... I will say theres a ton of rust under the car..

[tmack6]

http://www.3800pro.com/

[kevandkaye]

http://www.3800pro.com/

X2 on the link. Also, have you gone over all your vacuum lines? If you have a lot of miles, you can get a replacement set from the stealership for around $40 bucks.

[DKap7]

So I used my app Torque, and it said my MAF was messing up and my upstream O2 sensor... I also had a rondom miss problem.. So I swapped out the MAF, put in a brand new O2 sensor, and replaced all the spark plug wires with AC delco ones... I pulled the plugs and they looked fine. It seems to idle nicer here are some numbers I took from torque maybe one of you guys can tell me if these numbers are okay....

This was idle car was around 130 degrees...

RPM- 850 ish

Throttle- 0.4

Vacuum- -20.5in/hg

Intake manifold pressure- 32kpa

Massflow Rate- 3.5g/s

Timing advance -23.5 degrees

[dave89iroc]

the MAF is a common failure on these


when it acts up/wont start, unplug the MAF, it might crank slightly longer then normal, but will start and run good if this is in fact then problem

[WilliamE]

I am having problems with my Buick Park Ave. that has a 3800 3.8L Series II Engine.

For two years on and off I've had problems with this, finally after it got so bad that I had a coil pack fail, which I then replaced, and it ran ok until I decided to turn on the AC while letting it idle, I wanted to see if that still caused it to chuggle and stall, and it did, only this time it would not restart again.

I cleaned my IAC, and my MAF, as well as TPS, ended up also cracking my MAF while tapping it, but used silicone on it.
My IAC had a lot of carbon deposited on it, my TB was a tad dirty as well...

I had low fuel pressure, at least my mechanic said so, so I had the fuel pump replaced, and will replace the fuel filter soon, even though I have the right pressure now.

I had the crankshaft position sensor replaced, and it did not fix the issue, I found out that there was an issue with the TPS causing similar problems, so I was leaning towards that, till now...
I am thinking maybe the MAF went bad....

A friend said maybe the two O2 sensors needed replacing, but money is limited because I just gave the mechanic $430.00 which did not fix the issue.

Another thing I considered was the camshaft sensor, but I am not sure that is the problem..

Mechanic thought the PCM was bad, but I am pretty sure it would spit out all kinds of codes if that was the case....

If anybody has any ideas, or anymore insight on this problem, the help would be greatly appreciated!

[WilliamE]

After speaking to my mechanic a bit more I found out that he said he put a NOID light on the injectors and they are not pulsing.
They do have 12v though, and the resistance of each injector is at spec and the same.
The wire from PCM to injector was checked for continuity, and it is good.

I thought maybe my issue was a security issue for a while, but I learned that an error with something like the theft deterrent module would not shut the car down while running.
I went as far as to learn how to test the resistance of my key, then verify the same resistance coming from the ign wires to the harness under the drivers side kick panel, on the left side.
In my case my key is .681, at the harness mentioned, and at the TDM I measured .581 resistance, so I thought I had an ignition cylinder/security problem, I spliced in a .680 resistor to bypass that and see if that was the problem, but it was not.

Since my injectors are not pulsing I checked the blue wire coming from my theft deterrent module, and when disconnected it read 5V, when the TDM is put back on and the blue wire is back-probed with the key in the ON position, the wire reads 1.96v, I read it was supposed to be 2.50, but since it is dropping in voltage I'm assuming it is sending the signal to the PCM to fire the injectors.

I forgot to mention I did have a coil pack 3/6 fail on me recently, it gave a misfire on cylinder 3 code, right before it started for the last time, I replaced it and the 3rd plug, and it ran great till I cut the air on while the car was sitting/idling.

List of stuff replaced.

Fuel Pump (I have proper pressure, fuel pump relay, and injector fuse are good)
Crankshaft Position Sensor
Throttle Position Sensor

I cracked my MAF, due to thinking I may have fouled it since I run a K&N air-filter, I was tapping it...
I used high heat silicone on the crack, but am replacing it soon, it was dead before I cracked this....

I'm replacing my ignition control module soon just in case, I also cleaned a bit of corrosion off of where it mounts to..


I am coming close to breaking myself and the bank with this car, I paid a mechanic 450.00 to replace the CKP, and the fuel pump because it was low on pressure, that took 430.00 bucks, and still I have a dead car.

I've had the same idling/running problems as described by
DKap7, on occasion during warm seasons the car would not start after being driven till it heats up and shut down, after cooling it would start again.
Had a mechanic look at the car because once it happened while I was driving, it started sputtering, and loosing power, so I had it towed, once he got it there and tested it it ran fine, and had no codes.

A few times when it started and ran funny I pumped the gas, and it cleared right up...

This problem has been ongoing on and off for 3 years, and it finally killed the car, I am only at 136,000 miles, and while that may be a lot, it is a two owner car, I am the second owner, the first took very good care of it, so I'd like to get it back on the road.

If anybody has any ideas or insight as to what could keep my injectors from pulsing, the help would be appreciated.

[kevandkaye]

Has anything been mentioned about a fuel pump resistor? I know this seems to be a problem on the Regals. I haven't had any issues on my P.A., so I'm not even sure if there is one. But I've read before that this can be jumped, or bypassed to see if it's a problem.
If you join here http://www.regalgs.org/ you'll get more 3800 specific help. or here.

http://www.3800pro.com/

[WilliamE]

Has anything been mentioned about a fuel pump resistor? I know this seems to be a problem on the Regals. I haven't had any issues on my P.A., so I'm not even sure if there is one. But I've read before that this can be jumped, or bypassed to see if it's a problem.
If you join here http://www.regalgs.org/ you'll get more 3800 specific help. or here.

http://www.3800pro.com/

Do you mean the fuel pump relay?

If so, in my case I tested my relay, I took it out and used some speaker wire, a jump-start box, I touched positive and negative to the proper pins on the relay, with power going to the proper pins on the relay I used a multimeter & followed instructions on testing two of the other 3 remaining pins, and all checked out fine with it.

If you are talking about a resistor that an cause the fuel injectors not to pulse, then my car have the Passkey II, which has the resistor pellet in the key, I did a bypass on my ignition cylinder, I read you can also wire in the resistor bypass at the TDM, but mine are going to the wires that go into a harness under the driver side kick panel.


Thanks for the 3800 pro link, I was just registering there before I seen this thread had a reply. :)

[kevandkaye]

I meant resistor. I did some looking, I think the relay is for a two speed pump on W-body Grand Prix's and regals. But since I looked, here's a test for some who may see this in the future;

http://robertpurvis.snapontools.com/TechTips.asp?tip=15&DealerName=robertpurvis

[ern215]

i have a 2003 chevrolet monte carlo ss 3.8l v6 (3800)
i was on the freeway and looked at my dash and i noticed i was in the red (overheating) so i got off the freeway (880 east bay/oakland, ca) and let the car cool down, added water and got the car home, now im having a very difficult problem to solve, the car only stays runnign for maybe 5 minutes at a time and i have replaced:
1.crankshaft position sensor
2. battery
3. both coolant elbows
4. the connector wire to the front knock sensor was severed causing the "check engine" light to come on, this was repaired and the "check engine" light no lenger is on
the car continues to stall and i jus dont understand what this problem can be, i checked the fuel pressure regulatoe and there is no fuel backed up int the line so i am assuming that is not the problem.
any input/suggestions would be greatly appreciated.