[mycarver]

I have a 2000 Seville STS. Occasionally I have a starting problem where it turns over fine,,almost starts,and then stops. I restart and it spins a bit more than usual but does fire up. Seems a bit rough for a few seconds but clears itself up. The Check Engine light usually comes on at this time as well. This happens maybe once a month now.
I've pulled the codes which are:
DIM u1016 history
TTM u1016 history
and then
CLM p1072 and 1075

I'm not sure but it seems to indicate both left and right banks running rich. Is this correct, and if so what might you suggest the next course of action might be?
Other than this recent problem the car shows no other codes and is pretty much pristine since I've had it over two years now. OK,,a dead battery,,but it was the original..big deal,,but the symptoms did seem to start around that time. Any link to that?.
Thanks for any help you might be able to offer.
Mark

 

[Submariner409]

Remove the engine beauty cover and locate the FPR (Fuel Pressure Regulator) on the right rear of the fuel rail. There's a vacuum line from the regulator nipple to the throttlebody casting. Check that for integrity. Start the car and pull the vacuum line off the FPR nipple. If there's raw gas in there, that's your problem. Find your car and FPR in www.rockauto.com and click on the small picture or (!) icon for a larger picture. One hairpin clip and out it comes - 2 O-rings, lube with engine oil and slip it back in.

Otherwise, sticky fuel injector. Run a 20 oz. bottle of CHEVRON TECHRON through a half tank of fuel.

Google "chevron techron" and "top tier gasoline" to find out why...........

Try your DTC's again. There are no "P1072" and "P1075" codes, and CLM is not listed as a P module. ( ah, so........P0172/0175)

 

[N*Caddy]

I would go straight to the FPR (Fuel Pressure Regulator), especially if that occasional hard start is when hot.

UPS!
Sub beat me up...

 

[mycarver]

Wow,,,thanks guys! Such a quick response. Considering both of you seem to think it's the FPR,, I'll start there.
And yes,, a detail I failed to mention was that this only happens when the car is hot. Eg. shut it off, run into a store,,and restart it. That is the only times this has happened. You must have a good idea since you diagnosed this without me saying so.
Off to the garage to check this out..make the repairs and when done,, I'll let you know.
Thanks again!
Mark

 

[N*Caddy]

Unless you don't want to get gas on your fingers, is one of the simplest DIY possible (is harder to replace a wheel than the FPR).
If you decide to DIY then make sure to release the pressure from the fuel line or you can get gas all over (including but not limited to your eyes). Locate the Schrader valve situated at the end of your fuel line (looks exactly like a tire valve but twice larger, also has a cap on top).
Engine OFF
1. Remove engine cover
2. Locate fuel pressure releasing cap on your fuel line and grab a rag place-it all around the valve, remove the cap and gradually press on the nipple, gas will spray for few seconds until the pressure drops. Make sure all that spray is in the rag.
3. Remove the vacuum line from the top of the FPR and the clip Sub mentioned. The FPR should come up easily.
4. Follow Sub instruction regarding the O rings and push the new FPR in place then lock it with the clip and connect the vacuum line back.
5. Turn the key to ON (don't start the engine) and allow 5 seconds or so for the fule pump to restore the pressure on the line.
6. Look for possible leaks around the FPR (make sure the are around the FPR was dry before so no assumptions).
7. If all good put back the engine cover and enjoy the $50 you just saved

It does sounds complicated when you read-it but really is easier than replacing a tire.

 

[mycarver]

Well I started with the FPR. Had the car running,,pulled the vac line and saw no evidence of fuel. As I said though this happens only occasionally. But what did happen was I shut the car off..waited a few seconds and restarted it. It ran HORRIBLY. Sputtered and coughed,,blipped the throttle..cleared up but idle was up around 1100 or so,,gradually settled back to around 750 sounded like it might stall..but did clear up. Successive starts and this condition disappeared. Last try it started barely touching the key.( normal) The codes had been previously cleared,,so I pulled them again and only one came up. PCM p1106. It doesn't seem like a FPR would work intermittently ,,but I could be wrong. Do you think the problem still is there and should be replaced as "insurance". It's not a big deal to do as I did pull this one out of curiosity and the cost is minimal. Maybe that too is part of the hard start problem I just experienced as well having pulled it?

Ahh seems so. YOur post N*caddy got in under mine...I think I started it too soon without letting pressure build first..hence the stuttering and rough running initially. Now it starts just fine..barely touch the key. I think ( since I've done it already) I'll just replace the FPR as you say,, it's a simple enough job. And cheap insurance as well. one less thing to think about.
Thanks so much

 

[N*Caddy]

Well in the first stages (occasional hard hot start) the FPR nipple might not be wet, but providing the time...it will (that’s when every hot start will be hard). At least that was my experience.

 

[mycarver]

Yeah,,'Kinda figured after giving it some thought. Makes sense. I'll go that route and just replace it.
Thanks again for helping me take care of my "baby" . It's not a new one,,but I get a kick out of it still. for what it's worth,, here she is. Interior is perfect as well.

 

[Submariner409]

P1106 refers to MAP sensor, located on the throttlebody. In a soft rubber bushing/retainer. Pull the connector and remove the sensor, making sure the orifice in the tip is clear. Throttlebody cleaner, not choke cleaner.

mycarver, click on the little picture icon under my login header for other pictures of year 2000+ engine parts. (2 pages)

 

[mycarver]

Again,,,WOW,,glad I checked back before heading for the part ( FPR) . I'll pick up some throttle body cleaner as well (submariner409) for the MAP sensor . Thank you everyone for your input and advice. It's GREATLY appreciated. Hopefully she'll be running as smooth as ever. Getting plugs too,, she deserves a treat. AC delco platinum as other posts have indicated.
And I lied,,,I don't like this car,,,, I love it.

 

[Submariner409]

When you do the plugs you'll find that the rear coil cassette is a bitch to remove due to the A.I.R. valve and bracket. It takes some bending and twisting to unbolt the metal pipe flange down behind the head.

Make sure the upper coolant hose is clipped into the channel under the rear of the radiator sight shield or it will rub on the cam cover. The sight shield plastic rivets come out by lifting the center pin and pulling the rivet. Spares on the "Help!" rack at the parts store.

If one or more plugs have some oil on the shell, no sweat. The plug wells are sealed by O-rings and tend to weep. Not a problem.

Change the plugs with the engine cold, and torque to 13 ft/lb. Make sure the ground spring for each cassette is clean and makes good contact. Check the coil boots for their internal spring tension and carbon tracking. Use a tad of ignition dielectric grease on each plug insulator to allow the boot to seat easily. Take a look at P.1 of my album for plugs, boots, and coil cassette.

Find the RPO sticker under the spare tire cover and enter the codes into www.cadillacfaq.com/rpo/index.php to find out what's built into your car.

 

[mycarver]

More great tips from someone who as obviously been there. Thanks,, and the photo on page two (29) was helpful as well. Seems our cars are twins,,separated only by a few yrs. The rear bank looked "interesting" to tackle,,but I'm sure I'll figure it out as I go along. I've wrenched on cars for some time..but out of ignorance shied away from all the computer stuff. Your help gives me confidence. Remove and replace is one thing,,knowing WHAT to R&R is another.
The FPR will be in in 2 days direct from factory,,only $30.00 bucks. No brainer there. I'll play with the plugs this evening.
All info is appreciated. Thanks guys.