Replaced throttle position sensor, cam shaft sensor, crank sensor, tested ignition module, replaced fuel filter, along with idle air control vale, replaced coolant temp sensor spark plugs,wires, computer, replaced brake booster. trottle position sensor fixed cruise control works now. Car will stop idle surging and die only if you unplug vacuum line to charcoal canister any suggestions seems like vacuum system needs more fresh air to pull in ?????????????????

Just about the only thing missing from that list is the mass airflow sensor. I would recommend unplugging the sensor, and see what happens. It's going to run rough, but if it stops surging and dying then that points to that sensor.

Unmetered air (disconnecting the vacuum line) fixing the surging makes me think it's that sensor as well. Is there a check engine light on? I know the '94/'95 cars needed a specific scanner to read the codes, might be worth the investment. Certainly better than throwing parts at it.

_________________
Boost addict


The Fleet:
'93 SSEi - Twincharged + manual Build thread
'97 Camaro - Top swap
'05 STS - V8, AWD, her DD
'92 Trofeo - Fair weather DD
'99 Montana - top swap 3800
'04 Sierra 2500HD - LLY Duramax

Current project:
Something cool, trust me.

Upcoming projects:
'92 Bonneville SSE
'87 LeSabre T-type
'67 LeSabre

Gone to greener pastures:
'84 Sierra Classic - Twin turbo 3800
'97 LeSabre - Top swap

RIP:
'86 LeSabre - pictures
'93 SE - L67

In the past on other vehicles like my 99 bravada when you unplug the mass air flow sensor. The computer goes into back up mode and compensates for sensor being unplugged and basically diagnosis is easy if it runs better unplugged sensor is bad. This pontiac just runs terrible with mass air unplugged....?

Usually when the maf is bad, unplugging it does make the car run butter, but not in every case. When mine died, the car wouldn't run at all with it plugged in or unplugged. If you've got someone with another series 1 3800 you can try and swap sensors to test it without buying a replacement, but in most cases getting a used maf from a junkyard will be better than the reman units. I agree with matt, adding the extra unmetered air with the vacuum line pulled definitely sounds like the computer isn't reading the incoming air right, which points to the maf or iac, which you already replaced.

_________________



Joseph

Current: 2013 Infiniti G37 Journey
1999 Infiniti G20T - Sold
1999 Buick Lesabre - Race Couch - gone but not forgotten

I will give it a try thanks for your input guys.

Has the car ever been scanned?

Yes prior to computer replacement and new throttle position sensor it kicked out p0361 electronic spark timing not toggling and tps sensor never had it scanned since new parts though oreilly did it for free...

Also fuel mileage is terrible 112 miles per fill up this car also seems to be not shifting properly if taking off from a stop up hill i shift manually with shifter trying to help with fuel milage also car has never kicked down either under 35 mph floor it just slowly increase speed no trans kick down.already replaced trans modulator.

Well then, it could be a vacuum leak. A vacuum leak can give all those symptoms. - BC

_________________
In Memory of Brad - 1/21/1977 .. 10/23/2013 ...... Aaron - 1977 .. 2017 .....
2017 Hyundai Santa Fe Sport ..... 1992 Bonneville SSE 1SB 170 HP L27 4T60E retired/sold to MattStrike ..... 2005 Bonneville SE 1SC 205 HP L36 4T65E - retired/salvage yard ..... PBCF user 2321

Had car scanned today and...egr code kicked.

the P0361 more than most times ends up being a P1361..

The EGR code needs to be dealt with..

But from what you describe it seems as if you could have a bad TPS... On a 94 this is not adjustable.. The PCM needs the TPS to be 100% good for the trans and fueling to be correct..

Your fuel mileage should be way better that that as well.. Would you happen to know what type of O2 sensor is on your car? Generally for these cars we highly recommend an AC delco unit as the Bosch units tended to fail with the 3800's.. and iirc the 94-95 Bonneville used an AC Delco AFS-75