: Northstar - Starting Problems



rslanca
10-02-04, 11:39 AM
I have a '98 Concours and can't seem to find source of hard starting problem. Turns over for several seconds before it fires. Anyone else experienced this problem or have an idea what's causing it?

sts96
10-02-04, 03:05 PM
Hard start warm engine fuel pressure regulator leaking into vacuum line and intake, hard start cold engine low fuel pressure from pump. check for codes could be many other things. sts96

sseville
10-05-04, 09:40 PM
I have a similar problem as you do. As the colder weather moves in and I have the heater going for awhile and then shut the car off it dosen't want to start at all. What happens is it'l take much longer than usual cranking time and then when the engine fires it'l only fire for a second or two then stall. Usually it does this twice at which point I give it a little gas and even still the rpm's drop below 500 once or twice until I rev it up a couple times..........Just odd to say the least. :confused:

lonestar
11-11-04, 03:50 PM
I have a hard start when the engine is hot does anyone have any ideas

Ranger
11-11-04, 07:53 PM
I have a hard start when the engine is hot does anyone have any ideas
Check the FPR. Pull the vacuum hose off while the engine is running. If fuel leaks out of the nipple, replace FPR. If not FPR, then leaky injector(s).

exuberant anti-spam
11-18-04, 08:03 PM
What does FPR stand for?

Ranger
11-18-04, 08:18 PM
FPR = fuel pressure regulator. It is mounted on the right bank (rear) fuel rail.

ebs007
01-24-05, 12:38 PM
I have the same problem with my 97 STS. It starts fine cold, and usually starts ok if it's still hot (shut off within 10-20 minutes) but hard to start when warm. It will crank for a while, sometimes backfire, then eventually start. :banghead: It starts better if I give it a little gas while cranking. I'll have to check for the leaky FPR ... thanks for the tip! :coolgleam:

longisland516
01-25-05, 07:53 PM
I have a hard start with a 97 DeVille. This car currently has 118k. FPR, plugs, wires, and coil packs/module have been replaced and the car starts the same.

The car starts hard cold, below 30F. It cranks and seems like it is firing on one or two cylinders. I have to keep the starter on to prevent it from stalling once it starts to fire. This whole process is about 8 seconds. Sometimes it will stall. The computer usually increase the idle a lot just before the stall to try and compensate.

The fuel pumps runs for about 2 seconds when I turn on the key and everything seems to be fine. Sometimes it will miss on one or two cylinders for about 1 minute or until engine temperature reached about 40 degrees. The car always seems to start, even when the temp is 0F. It has had this condition for the last year and 18k miles.

The car runs 100% perfect after this and runs perfectly smooth with no hesitation. Fuel economy is 23.6 mpg average for the entire last year. It runs 0-60 in 6.4 seconds and sounds great doing it. There are no codes set and have been none for the last year.

Any ideas as to why this car starts hard when cold?

mcowden
01-25-05, 11:13 PM
I'm not saying this is the source of anybody's starting issues here, but I'm just sharing the anecdote because the difference was surprising.

I changed out plugs and wires at 90k because of a misfire problem that was getting worse. I used the AC Delco 41-950 plugs and AC Delco wires as recommended passionately on these forums. The plugs that were in there were Bosch. I can't say I really had any serious starting problems with the car, but it did take some crank time, especially in cold weather, before the tune-up. Since doing the tune-up, it starts almost instantly, even when the temp is near 0F. The difference is amazing to me. I can't say it was the plugs or it was the wires because I changed both, but I'll tell you, I was really surprised by the difference.

Maybe that'll help somebody. I won't use anything but the AC Delco wires and plugs in the future. Yeah, it was a few bucks more, but so far it was worth every penny. Best prices I found for them was at www.rockauto.com. The wireset was about $116 I think and the plugs were $5.89 each.

The fuel pressure regulators can be tested. Take off the vacuum line going to the FRP and idle the engine for a few minutes. If you see fuel seeping from the vacuum nipple on the FPR, the diaphragm is bad and the FPR needs to be replaced. That will solve some hot restart problems.

Good luck one and all... Check your codes and let us know the details of the problems and somebody will likely be able to help you fix it up.

BeelzeBob
01-25-05, 11:25 PM
I have a hard start with a 97 DeVille. This car currently has 118k. FPR, plugs, wires, and coil packs/module have been replaced and the car starts the same.

The car starts hard cold, below 30F. It cranks and seems like it is firing on one or two cylinders. I have to keep the starter on to prevent it from stalling once it starts to fire. This whole process is about 8 seconds. Sometimes it will stall. The computer usually increase the idle a lot just before the stall to try and compensate.

The fuel pumps runs for about 2 seconds when I turn on the key and everything seems to be fine. Sometimes it will miss on one or two cylinders for about 1 minute or until engine temperature reached about 40 degrees. The car always seems to start, even when the temp is 0F. It has had this condition for the last year and 18k miles.

The car runs 100% perfect after this and runs perfectly smooth with no hesitation. Fuel economy is 23.6 mpg average for the entire last year. It runs 0-60 in 6.4 seconds and sounds great doing it. There are no codes set and have been none for the last year.

Any ideas as to why this car starts hard when cold?


You really need to get a fuel pressure gauge on the rail and watch the fuel pressure DURING CRANK ON THE COLDSTART. If the fuel pump is starting to fail it will usually draw lots of current and will loose effectiveness when the system voltage is low....like during the cold crank when the starter is drawing the battery voltage (and fuel pump voltage) very low. It is not unusual to see 7 or 8 volts at the fuel pump during cold cranking so if the pump is weak at all it will just not put out..... The fuel pressure should pop up to about 50 and hold steady during crank.

Try opening the throttle to see if that helps.

To test for a rich condition causing a hard start warm/hot hold the throttle firmly to the floor before cranking and keep it firmly depressed when you crank. This enables clear flood and turns off the injectors. If the engine starts immediately then something is flooding the engine such as the FPR or a leaking injector.

longisland516
03-15-06, 07:32 AM
You guys were correct; the problem was the fuel pump. It finally failed at around 140k miles. Installed a new ACDelco and the car starts like the day it was new, at any temp.

donclericuzio
03-15-06, 01:44 PM
I have had the same problem and got it clarified when I was finally up to Cadillac to get my shinny new fuel rail!!! And also they replaced a airbag sensor as well!!! He calls me thought in the middle of the fix and tells me about the fuel pressure regulator,says total labor and part about 120$ anyways I didnt have the funds at the time to get it fixed!! So I was wondering if the leaking of the FPR could cause the rought engine idle, at stop lights it sometimes runs smooth at about 700rpms and sometimes surges all the way to like 1200-1300 with out touching the gas. It also sounds like maybe a timing problem posibly or maybe a vaccum hose?????!!!!?????

Ranger
03-15-06, 05:26 PM
I have had the same problem and got it clarified when I was finally up to Cadillac to get my shinny new fuel rail!!! And also they replaced a airbag sensor as well!!! He calls me thought in the middle of the fix and tells me about the fuel pressure regulator,says total labor and part about 120$ anyways I didnt have the funds at the time to get it fixed!! So I was wondering if the leaking of the FPR could cause the rought engine idle, at stop lights it sometimes runs smooth at about 700rpms and sometimes surges all the way to like 1200-1300 with out touching the gas. It also sounds like maybe a timing problem posibly or maybe a vaccum hose?????!!!!?????
I am not sure if a FPR would cause a rough or fluctuating idle or not, but you can get one for a lot less than $120. They are easy to diagnose and change (see Tech Tips section).

Zorb750
03-15-06, 11:34 PM
FPR can cause odd idle patterns. It did on the Eldorado.

ajc3579
09-11-10, 07:20 PM
I have this same problem. Did you figure it out?

Floyd
09-22-10, 04:49 PM
I'm having an issue with my daughters 93 El Dorado, it's not starting. When cranking the engine will hit but not catch. The engine was running fine and just dies on her and since the only time it will run is is you squirt a little starting fluid into the throtle body, it will run until fluid is gone then nothing.

Ranger
09-22-10, 08:44 PM
it will run is is you squirt a little starting fluid into the throtle body, it will run until fluid is gone then nothing.
The fuel pump is D.O.A.

bicycledon
10-23-10, 11:26 AM
Hi,
I have a 98 DEville, less than 30k. has been sitting for a few years. Runs great, like a new car. I put about 3k of daily driving on it now. NNow that weather is getting cold it starts hard in the morning only. Fires up fine all day long. Any advise?

Submariner409
10-23-10, 01:02 PM
Hi,
I have a 98 DEville, less than 30k. has been sitting for a few years. Runs great, like a new car. I put about 3k of daily driving on it now. NNow that weather is getting cold it starts hard in the morning only. Fires up fine all day long. Any advise?

Possible that the FPR (Fuel Pressure Regulator) is bleeding down system pressure overnight - at tomorrow's start, turn the key ON but do not try to start; turn it OFF for 10 seconds, turn it ON, pause, then try to start it. This will prime the fuel rail IF pressure has bled down.

If no joy there, then you may be in the "tuneup" business - plugs (ACDelco Platinum #41-950 ONLY), throttlebody cleaning and air filter. At 30K you should not need a fuel filter (under the rear passenger door at the frame inner rail).

bicycledon
11-29-10, 11:43 AM
Thanks submariner, Your advise helped locate the problem with the FPR. The start check made it start fine. Bought a FPR a month ago, but did not install untill yesterday. Starts great now, even in the cold Michigan weather, easy to install, took just a few minutes. However when done the check engine light came on. Any concern there? Car runs great, been on highway, 23 plus mpg, 19 in city.
peace,
Bicycledon

Submariner409
11-29-10, 12:04 PM
Hmmmmmm..............Learn to use the system discussed in the sticky thread "How to pull codes" at the top of the main Northstar Performance - Engines page to pull your DTC's from the car's built-in code scanner/reader. A SES light is always set by a P Diagnostic Trouble Code.

brangwinj
04-23-11, 12:09 PM
I had a similar problem-- read in Paper fromCar Guys( same guys on npr ) mentioned the crank case sensors possible cause NS has 2 replaced them problem cured for 4 weeks then yesterday tough starting again maybe the cam sensor I am just throwng parts now

RippyPartsDept
04-23-11, 12:28 PM
that crank sensor problem was on 2000-2005 devilles and 2000-2004 sevilles

and there usually wasn't any problem w/ starting but the cars tended to stall at stop lights or when coming to a stop

Ranger
04-23-11, 08:45 PM
I thought it was 2000 - 2003. :hmm:

RippyPartsDept
04-23-11, 08:48 PM
yeah you're right... i was listing the body-style years because i didn't remember exactly what year they went to the japanese sensors

RippyPartsDept
04-23-11, 08:49 PM
brangwinj,

do you have a check engine light on? have you pulled the codes from the dash with the onboard scanner? (see the sticky)