'99 SE stalls and dies at low speeds and idle

[robodude666]

Would a fuel pressure gauge/tester kit like this:

http://www.walmart.com/ip/Equus-3640-In ... r/14644670

work out? It has GM adapters, plus it has a bleed like to relieve pressure after testing. I figure I should get a gauge so that I can test the pressure, which would allow me to test the fuel pressure regulator, plus see if the fuel filter is clogged or my pump is going out.

-robodude666

[RPACODY]

should work out ok - good idea to have FP teser

[robodude666]

Okie dokie.

So, I got the fuel pressure gauge today in the mail and tested my bonneville's fuel pressure. Here's what I found:

When the car is on the ignition, the fuel pressure stays around 48 PSI. After the engine is turned on, it drops down to 46. The needle then violently jumps back and forth between 46 and 54 for a couple of seconds, and then stays steady at 46 again. After reving the engine while in neutral, the needle rests at about 44. If the vacuum hose is disconnected, the needle jumps to 55-58 PSI. After the car is turned off, the pressure drops to 42 and slowly goes back up to 52.

Normal fuel pressure for a 1999 bonneville should be between 48 and 55 PSU, from what I understand. Also, these appear to be the symptoms of a bad fuel pressure regulator. The pressure builds up very quickly, and does not drop, which suggests the pump is working fine; the fuel filter is not clogged, and the fuel delivery line is not clogged or kinked. Because it's unable to stabilize, the regulator is not doing it's job. That is, at least, what I understand based on watching a number of videos on YouTube and other readings. What do you think?

A couple of other things, really quickly:

- I relived the pressure before attaching the gauge, and I had a rag under the valve to catch any fuel that might come out. However, a small amount did manage to leak out and ended up on the engine (near the bolts to the intake manifold). Is that dangerous? How long should I wait before driving the car around? Gasoline evaporates quickly, and the car's hood was up the entire time for at least a half hour.

- Second, how do I dispose of the fuel that came out of the bleed line? I have it collected into a plastic water bottle. It's a small amount of fuel, but I know I can't just throw it out. Will a gas station accept it, or do I have to contact a waste disposal center on monday? In the mean time, where's the best location for storing it?

-robodude666

[RPACODY]

can't be much fuel would evaporate quick - if clean put in back in the car or a mower.
sounds like your fuel pressure is ok will jump about 10psi with change in vacuum .still thinking FPR because you said you smelled fuel in the vacuum line. Could have a diaphragm leak and still maintain pressure. If you smelled fuel in the vac line time to change the FPR!

what is the fuel pressure after sitting 30 min

[robodude666]

This is the Fuel Pressure Regulator that AutoZone recommends for my bonneville:

http://www.autozone.com/autozone/parts/ ... 63846_0_0_

I see that it includes a new snap ring, but what is the other silver item that it includes? Also, what size snap ring pliers do I need? I looked on Harbor Freight's website and they have different sizes, such as 0.038", 0.047", and 0.070".

-robodude666

[RPACODY]

looks like a retainer you probably need to change it out - something’s you need to figure out - go to the parts store and get cheap snap ring pliers with Multi head inserts - you need small don't know size off hand what ever fits the holes on the snap ring.

I'm just a old school guy with past experience and don't have all the detail answers you want. I just do it...

[robodude666]

I just got back from the stores. Got a new FPR from AutoZone, and snap ring pliers from Harbor Freight.

I'm going to let the engine cool down, and replace it later tonight or tomorrow morning.

What are the chances of replacing the FPR and it fixing my MAF error code? I'd rather not have to replace a $140 part also.

-robodude666

[RPACODY]

Bad FPR is like a fuel flood condition too much fuel at times – mine gave me secondary codes that went away. I would change the FPR and see how it runs - if better then disconnect the battery to clear codes and see if any return.

[robodude666]

Okay.

I relieved fuel pressure, and connected the fuel pressure gauge to the car. I disconnected the vacuum hose, and used the snap ring pliers to remove the snap ring, after which I wiggled the fuel pressure regulator out. I also removed the o-ring. There was a small filter that I was unable to remove, so I left it there as it appeared intack. I removed the filter that came with the new one, as I used the old one, and wiggled the new FPR w/ its new o-ring into place. After it was seated nicely, I put the snap ring back into place. I noticed that the FPR was able to wiggle in place a little bit. I thought this was strange as the old one wasn't able to wiggle previously.

After starting the car back up, I let it run for a few seconds to make sure there were no leaks and then I turned the car off. While running, the fuel pressure gauge was jumping all over the place again between 44 and 54 PSI very quickly. Upon turning the car off the gauge dropped down to 0, which I found strange as it previously kept its pressure on the tests I did on saturday.

I removed the new FPR and installed the old one, and the same things happened: It wiggled around; PSI wasn't steady upon turning the car on; after turning the car off pressure dropped to 0.

Did I do something wrong? Is this supposed to happen? I'm afraid to leave the car on longer than I did. I also am afraid to remove the original little filter as I don't see a way of removing it without breaking it -- it's really snug in there.

-robodude666

[RogueSSEi]

Ok, I've been reading bits and pieces of your problem. Here are a couple of links that I have gathered for you so the troubleshooting can be narrowed down a bit more. It could be a bad ground, clogged cat, dirty TB and sensors, bad O2 sensor. But first try these steps for the MAF cleaning, then we'll use some process of elimination. I'd run the fuel almost to completely out then put 92+ in it (depending on the highest grade available) with a fuel treatment mentioned in the Maintenance section.
Here is a link to a UIM and LIM gasket change, in this information you will find how to remove and clean the MAF, but if you can get the MAF sensor off clean it with MAF cleaning spray, Take the IAC and clean it like mentioned as well. viewtopic.php?f=53&t=3591

Remove and clean sensors At the throttle body, undo the electrical connectors for the MAF (mass air flow sensor), TPS (throttle position sensor), and IAC (idle air control) valve. MAF: Using a small security torx tool, remove the two screws for the MAF and carefully twist and lift it out of its hole. Gently clean the wires with rubbing alcohol and a Q-tip, or spray with special MAF cleaner. Set it aside where you will not step on it. It costs $150.



IAC: Using a screwdriver blade that fully fits the slot, remove the two screws securing the IAC. You may need to use a little penetrating oil as you go if the screws were secured with thread locker. Take your time. You do not want to break one of these off in the aluminum throttle body. Clean the pintle and spring of the IAC with a safe solvent like brake cleaner or throttle body cleaner. Do not push the pintle in. It is attached to a stepping motor. Do not spray cleaner up the spring toward the motor.

• 1987-2005 Bonneville / Buick 3800 Maintenance List
  
  Run Seafoam, Chevron Techron or Gumout Regane through gasoline every 5,000 miles.
  
  Grease: Ball Joints, Tie Rods Every 8-10k ( Green Grease or Amsoil Grease recommended)
  Air Filter Every 15k (Amsoil EaA, Purolator PureONE)
  PCV Valve Every 30k
  MAF Sensor Element Cleaning/TB Cleaning Every 50k viewtopic.php?f=48&t=1661
  Fuel Filter Every 15-25k (Purolator, AC Delco, WIX) http://www.pontiacbonnevilleclub.com/fo ... 45&t=23215
  Spark Plugs Every 30-50k (NGK TR55, AC Delco 41-101 or Autolite 605) (Never Bosch)
  Ignition Wires Every 30-50k (Napa Belden, AC Delco, Autolite Pro, NGK) (Never Taylor or Bosch)
  Oil & Filter Every 5-6k or Every 6 months (Valvoline SYNPower, Pennzoil Platinum, or Amsoil )(Mobil1, Purolator PureONE, Amsoil EaO, K&N or WIX) (Never Fram) viewtopic.php?f=45&t=214
  *Conventional Oil Every 3k/3 months(API SM/SN rating) (WIX (Napa), Delco or Purolator filter)
  Tires: Check Inflation Pressure & Visually Inspect Monthly Rotate Every 6-8,000 Miles
  Transmission Flush or Pan Drop Every 15-20k (Always make sure filter is changed when flushed) viewtopic.php?f=45&t=10193
  Cooling System Flush Every 25-50k or 3-5 Years (Peak or Prestone Mixes-With-Any Coolant Only) (Never Dexcool)
  Oxygen Sensor Every 80-100k (30k for non-heated) (AC Delco or Denso) (Absolutely never Bosch) viewtopic.php?f=48&t=794
  Accessory Belt Inspect every 15k, replace every 100k, or as needed
  Cabin Air Filter Inspect and Replace every 15k, or as needed in dusty conditions. (Note: 00+ Only) viewtopic.php?f=45&t=13626
  Evap Core Cleaning Whenever Needed (Note: 99 and older only) viewtopic.php?f=45&t=2432
  Brake Fluid Flush 3yr/50k
  Power Steering Fluid Replacement/Flush Every 100k or 5 years
  
  *Special Considerations*
  All Series II/III 3800's RPO's: L36, L26, L67 & L32, especially important on vehicles factory installed with orange Havoline Dexcool Antifreeze/Coolant: http://www.dex-cool.net/
  Lower Intake Manifold Gasket Replacement, every 80-100k (ignorance of this can allow coolant to enter your engine oil, this happening can cause irreversible lower engine damage, requiring replacement of subject engine)
  
  Series II, Naturally Aspirated, RPO:L36:
  Upper Intake Manifold Plenum Replacement, Every 80-100k (ignorance of this can allow coolant to enter your intake manifold, possible damage to occur can be hydrolock, irreversible damage to emissions devices, misfires, etc. Most times, engine replacement is required if ignored long enough.) viewtopic.php?f=53&t=1061
  
  Series I, II, III RPO Code L67 & L32:
  Change Supercharger Oil; Every 30-50k. (Intense Racing or GM Dealer) viewtopic.php?f=56&t=1690
  Supercharger Belt; Inspect Every 15k, Replace Every 100k or as needed.

3/2/12 by 00Beast

[RPACODY]

need to get the FPR installed and working 1st

[RogueSSEi]

Autozone Duralast
--AC Delco please

[robodude666]

Okay guys. It's been some time since my last report.

I replaced the FPR with the new one, using the new parts included with the FPR. I also had the oil changed. The new oil is Valvoline Maxlife 10W-30, based on recommendations I found around the forms (it was also cheaper than SYNPower). I also had the oil filter replaced, as well as the air filter, and fuel filter. The positive battery terminal was also replaced as it was completely corroded. The car runs much better but the stalling at idle problem persists.

The IAC motor/valve appears to be extremely hot after running for a while. If the IAC's cable is disconnected, the car dies instantly after turning on. I still haven't acquired throttle body cleaner, so I haven't taken the TB apart and cleaned the TB, IAC, and TPS. I will be doing this sometime this week.

Has anyone else experienced the IAC motor/valve getting very hot? Is this something that would suggest the part is malfunctioning and needs to be replaced, or would a simple cleaning help mend the heat? Unless, of course, it's normal for this part to be hot.

Also, after replacing the fuel filter there was a leak at the quick disconnect coming from the fuel filter. After a period of time, the leak disappeared. I read that you're supposed to use engine oil to seal the quick disconnect before installing the fuel filter. Is this a necessary step, or can be bypassed?

Thank again for all your help.

-robodude666

[RogueSSEi]

Okay guys. It's been some time since my last report.

I replaced the FPR with the new one, using the new parts included with the FPR. I also had the oil changed. The new oil is Valvoline Maxlife 10W-30, based on recommendations I found around the forms (it was also cheaper than SYNPower). I also had the oil filter replaced, as well as the air filter, and fuel filter. The positive battery terminal was also replaced as it was completely corroded. The car runs much better but the stalling at idle problem persists.

The IAC motor/valve appears to be extremely hot after running for a while. If the IAC's cable is disconnected, the car dies instantly after turning on. I still haven't acquired throttle body cleaner, so I haven't taken the TB apart and cleaned the TB, IAC, and TPS. I will be doing this sometime this week.

Has anyone else experienced the IAC motor/valve getting very hot? Is this something that would suggest the part is malfunctioning and needs to be replaced, or would a simple cleaning help mend the heat? Unless, of course, it's normal for this part to be hot.

Also, after replacing the fuel filter there was a leak at the quick disconnect coming from the fuel filter. After a period of time, the leak disappeared. I read that you're supposed to use engine oil to seal the quick disconnect before installing the fuel filter. Is this a necessary step, or can be bypassed?

Thank again for all your help.

-robodude666

Don't worry about the fuel filter issue, mine did that and went away after I changed it so don't worry about it, as long as it has stopped you will be fine, and don't use any type of oil as this will lead to fuel contamination. I would get a can of brake cleaner for the IAC and read CAREFULLY about how to clean it, DO NOT spray up into the IAC plunger spring, clean this really good with brake cleaner, then clean the MAF with MAF cleaner spray. After doing this see if this improves the problem, good luck

[robodude666]

Hey guys,

It's been some time since my last post. The car is still having issues, but being without a job, I haven't been able to invest any money to attempt to fix it. Lately, the car has developed some other issues which may explain my existing stalling issues.

The car is leaking radiator fluid from the engine block itself. I'm unsure if it's from the lower or upper intake manifold area, but it appears there is fluid coming out from the side of the engine assembly and onto the ground. This general circled area is where you can see a good puddle and a lot of wetness when the leak is occurring:


(Click for a larger image.)

The leak is strongest after the reservoir is filled up to the line. If you leave the reservoir and radiator alone, the leak stops after a day or so (but will resume again after the car is turned off after driving for some time). It mostly leaks while the engine is off, but cooling down -- probably because there is still a lot of pressure in the radiator. I have checked the engine oil to make sure it wasn't leaking into the oil. The oil stick smells only like oil, and the oil level is just at the "Full" marker, where it's been since the oil was changed - a month or so back.

I have read through this thread related to information on the upper/lower intake manifold/gasket issues with the 3800 Series II Vin K engine I have. I took a look at the manufacturing date on the upper intake manifold as discussed in the article. While I was unable to make out the month/date, the year was marked as "98" which would suggest either: A) The car is running with the original manifold, or B) a replacement part from 1998 was used. I'm guessing A is more likely. What do you guys thinks? What’s the chance of it also being the original gasket? When I purchased the car new, the radiator and radiator hoses were recently replaced.

Based on the article, I have come across these two kits:

http://www.ineedparts.com/auto-parts/in ... 17806.html

http://www.autozone.com/autozone/parts/ ... 7105_7559_

Both kits look complete. The Dorman kit is talked about in the article I linked to above, while the "Sure Fix" kit is not. I like the "Sure Fix" kit more as it's A) cheaper, but B) supposedly does something that fixes the issue from occurring again. These two kits assume it's the upper intake manifold & gasket that needs to be replaced. I haven't really seen any lower kits for sale.

Which would you recommend?

Because of the disassembly required in order to get full access to the intake manifolds & gaskets, I feel very uncomfortable performing the replacement myself. If I were to go to a mechanic with my parts, how much would you expect them to charge me? Or, approx. how many hours of work will it be?

Also, this may be unrelated to anything -- or it may very well be related -- but, the AC Compressor (from what I understand it to be) is making a whining noise when the car starts up and keeps doing so for a while. I believe it's the AC Compressor as it resembles component #5 in this diagram, both by location and appearance:



Thank you very much for all the help you've provided, and look forward to one day fixing these darn issues once and for all.

-robodude666

[myfirstbonnie]

The coolant leak is most likely the coolant elbow. You can barely see it in your picture, but it is right there, a small plastic elbow that tends to deteriorate and eventually leak from cracks or a bad o-ring.

The best UIM to get is the first link you posted. It has the insulating sleeve for the EGR gases to protect the plastic a little better.

Yes, the AC compressor is #5. You will need to have the system evacuated before replacing it and then recharged after.

[robodude666]

Hey,

Would this diagram represent my 1999's engine accurately?


(From this post.)

If it does, the elbow you're referring to is marked as #1? How would I go about testing whether or not the leak is coming from the elbow?

This part doesn't seem included in the UIM kits, is that right? If it doesn’t, what part is recommended for replacement? I can’t seem to find any online.

Would it be recommended to replace the UIM while replacing this elbow, or would replacing the elbow itself be sufficient of a fix? If the car was taken to a mechanic, how many hours would replacing the part take?

I also want to note that the coolant also only leaks when the reservoir is above "FULL COLD" while the engine is actually hot. I'm not sure if that helps with the diagnosis, but I found it interesting.

Thanks again,
-robodude666

[myfirstbonnie]

If it does, the elbow you're referring to is marked as #1? How would I go about testing whether or not the leak is coming from the elbow? By watching it over several days you will see if it is leaking

This part doesn't seem included in the UIM kits, is that right? If it doesn’t, what part is recommended for replacement? I can’t seem to find any online. No, they do not come with any kits. They are available in the help section at most parts stores


Would it be recommended to replace the UIM while replacing this elbow, or would replacing the elbow itself be sufficient of a fix? If the car was taken to a mechanic, how many hours would replacing the part take? If it hasn't been replaced before, it is probably due along with the LIM gaskets. One of those things that is better to be replaced before it fails. As for time, a good reputable shop should not take too long to replace the LIM, but I don't really know because I do all my own work and when I did the last one it took us 10 hours (we had lunch and other breaks in between)


I also want to note that the coolant also only leaks when the reservoir is above "FULL COLD" while the engine is actually hot. I'm not sure if that helps with the diagnosis, but I found it interesting. Anytime there is a coolant level change, it should be investigated for leaks or burning.


Thanks again,
-robodude666

[robodude666]

Hey guys,

It's been a few months since my last post here. I got a job last month, so I can now afford to look into this more. Though... it wasn't really bothering me that much, but after almost getting hit by a car on the highway after my car stalled last week I decided to finally fix it.

I bought a new IAC and TPS sensor from RockAuto since they were both like $34 each.. Figured it's not too much of an investment. I got them in the mail on thursday, and finally got around to working on the car this morning. Before blindly installing a new sensor, I decided to buy $3 TP cleaner to clean my current IAC as suggested for a sanity check... Lo and behold cleaning the *dang* IAC worked! The car still hates backing up (it goes "put put put" when idling in reverse or moving slowly). When breaking for stop lights, stop signs, etc. the RPMs still dip below 500 - 800 but the car quickly brings them back to 800 - 1000 and stays fine. The car no longer "burps" when idling at a stoplight.

Now the question is:

- Do I return the parts I bought, or do I replace them for the hell of it?

- What will I need to do to completely fix the problem? No more "put puts", and no more RPM dips when breaking. I'm thinking about cleaning around the butterfly valve in the TB, but not sure what else I can look at.

EDIT:

False alarm. Car still stalls with the cleaned (old) IAC. It does it far less frequently now, at least. It seemed to be fine all day until the car's engine hit around the 200f mark. Should I try replacing the IAC/TPS with the ones I got from RockAuto? Or attempt to first clean the TB a bit?

Thanks,
-robodude666

P.S. Car stopped leaking radiator fluid randomly a few weeks after posting here.

[1oldman]

I have had a similar problem in the past. The "easiest" and most inexpensive thing I would suggest that worked for me is pull off the TB, remove all the sensors from the TB including the screen and give the TB a really good bath in hot soapy water with Dawn dish soap. Use an old toothbrush to clean the TB. Blow it out with compressed air and repeat several times. I alternated with TB cleaner between each bath of hot soapy water. There is also the possibility your Oxygen Sensor is compromised with the Seafoam use if you didn't remove it before running it through the engine. - BC