: AIR pump on '99

03-26-14, 12:46 PM
Hello Everyone,
I read a post here about at start up there was a rough idle for about 30/45 seconds and the
reply was that by pump, air is forced into the Cat on start-up and that made it smooth. correct me if not
quite on it. I checked Rock and Alldata and did not see any info. Does a '99 eldo w/ Y have this?
That's what mine does. In the AM I'll start it, gently slip it in gear and let it roll out of the
garage, then neutral until it clears the garage (because it stinks), by the time all that happens
idling smoothly. I don't believe its anything drastic but I would like it to operate properly. I'm
getting 21mpg at average speed of 29mph so there shouldn't be much wrong.
Could a faulty B2S1 be responsible? It is only about 2 yrs old when I clear the code it stays off
until I really jump on the gas.
Josie my shepherd and I like cruising in our Eldo:usflag:

03-26-14, 02:03 PM
The AIR pump does pump air into the cat during a cold start. It's to help the cat reach operating temp quicker. It has nothing to do with how the car runs/idles.

Have you pulled your codes recently?
Are you having to add coolant?

03-26-14, 02:37 PM

Could a faulty B2S1 be responsible? It is only about 2 yrs old when I clear the code it stays off
until I really jump on the gas.
Have you checked for a leaky FPR?

03-26-14, 05:02 PM
Hey Ranger, no I have not checked that , but I will shortly after you explain to me what it is, please!
I'm just learnin' things left and right this week, keep it coming I've got room..:confused:

03-26-14, 05:18 PM
In any forum of interest, always study the sticky posts just above these threads - FPR ?? The Acronyms sticky.

Begin by going to the top black bar and study the entire Cadillac Technical Archive. Then study the stickys in Discussions, Item Specific; Cadillac Tech Tips. The engine, cooling system, gauge and fan stickys in Engines; Northstar.

Find a real GM/Helm service manual set on eBay. Haynes or Chilton are far, far too generic.

Learn about DTCs, RPOs, TSBs and if available, read the owner's manual - twice - or download one. (Those stickys again !)

That's enough homework for today. More tomorrow ........... :)

03-26-14, 09:01 PM
The FPR (Fuel Pressure Regulator) is a small canister on the fuel rail with a vacuum line on top. Simply pull the vacuum line (red arrow) at idle and look for any sign of fuel at the nipple. There should be none.

Yours may be a nylon rail (yellow arrow) like this. If not, it will be black steel.

03-27-14, 11:22 AM
Thank you MoistCabbage for your response and the lession, Does my '99 even have a pump? I've looked in rock and
alldata and could not locate any. If it does not it is one less thing to worry about.

Ranger thanks for the pic, it took the uncertainity out of where and what it looks like.

Sub, thank you for reminding me of the sticky's..you can send me homework anytime...I----must----learn----more!
helm.com is next

03-27-14, 11:45 AM
You have a few extra bucks ??? For instant gratification take out a multi-year subscription to www.alldatadiy.com (http://www.alldatadiy.com) - it's the GM service manuals plus so darn much more that you need a course in how to find it all. Several of us use it.

For starters, in addition to being the service manual, it has all RPOs, TSBs, Recalls, labor times, warranty labor times, original parts pricing and diagnostic trees for YOUR car.

When someone posts "Look at the oil consumption TSB !" - it's there. "What's the RPO for my radio ?" - it's there.

03-28-14, 12:22 PM
Thanks Sub, The extra money would certainly be worth it for all that other info...thanks everyone ....Ed