FAQ: Rough / Slow / No Start - Symptoms, Causes, Solutions

AA wrote:

I would suspect a small leak in the fuel rail or line. May want to attach a fuel pressure gauge to the rail and see what happens after you shut off the car. It should hold above 40 PSI (or more) hours or even days after the car is turned off.

Look under the hood for a leak. Do you smell any fuel?

Yep, one of your injectors is most likely leaking down into the engine. As AA said, attach a fuel gauge, prime the fuel system, then turn the key off. Record the fuel pressure and let it sit for a few hours. When you come back check to see if the pressure is down. If it is low, then we can find the leak from there....

I second what AA said, that sounds like a leaky fuel line.

Thanks a lot you guys! The pressure is fine, and even if it was low, the minute you turn the key, the fuel pump starts, so pressure goes hi again ...from 40 to 50

How can I check the injectors ?If you think that it could be the problem.
Thanks again for the replies:)

Does the pressure stay up after you shut the key off?

Hey Philippe here is a link to an ehow.com page, it will tell you how to test an EFI system. If that leads to no luck I would take the fuel injectors out and have them bench tested at a shop with a fuel injector tester/cleaner. http://www.ehow.com/how_4798806_check-fuel-injector.html. Hope that helps!

I will be doing the tests this week, I'll get back to you soon.
Thanks

I noticed that writeup posted about injectors doesn't show an actual resistance reading for the injector....it just says "resistance measured". Proper injector resistance COLD is between 11-14 ohms. Aside from pulling the fuel rail and inspecting the injectors, really the only other way to test em is to do an injector balance test with a scan tool and a pressure gauge.
An injector that is shorted or "stuck" would more than likely throw a code, and the car would misfire ALL the time. A leaky one would cause a pressure drop over time without causing a misfire.

Hi guys!

Well so far so good, The pressure is fine and keeps it's hold. Now I will check each injector!!

This car has been driving me nuts since I got it. I orinally bought it with a bad fuel pump. The new one is in and putting out 50 psi. The car still won't start. It cranks and sounds like its going to start, but doesn't. It has spark, I changed the plugs and wires, and it is getting fuel. The plugs keep fowling up. It almost sounds like the timing is off. When cranking it makes sounds like its going to catch, but never does. Theres no codes in the computer, and it registers RPMs on my scanner when cranking, if that helps. I also tried swapping the ICM with a known good one.

did you ever check to see if you were getting any signal at all from the crank and the cam sensors?

did you ever use NOID light to check injectors?

did you ever actually fix your PassKey problem? (other than the 10 min battery disconnect - you can't do that every time you want to start, you need to fix or disable passkey)

Your plugs will get wet if run with no spark - but fouling?!? don't they have to fire to foul? doesn't your car have to run in order to get the plugs to fire?

Albertj

No, I don't know how to check those sensors.

I used a NOID light, it blinks for each injector

The Passkey issue was on my other riviera, the security light is solid and not blinking

I meant the plugs are drenched with gas when I pull them out

And one other odd thing. After I crank this car it for some reason smells like paint. I know it sounds weired, but it does. The gas does smell like gas!

moldymac wrote:

No, I don't know how to check those sensors.

I used a NOID light, it blinks for each injector

The Passkey issue was on my other riviera, the security light is solid and not blinking

I meant the plugs are drenched with gas when I pull them out

And one other odd thing. After I crank this car it for some reason smells like paint. I know it sounds weired, but it does. The gas does smell like gas!

OK, one item at a time.

1) the output of the crank and cam sensors can be read with a Tech II. An alternative to the Tech II is the Car Code program from Alex Peper. Car Code will read these values (link points to list):

http://www.obd-2.com/gmpida.htm

Car Code is free and you can make your own interface or buy one from Alex. (I bought one).

2) OK on the NOID.

3) Security light... As a rule, if the engine cranks but does not start, the Pass-Key system isn't causing the no-start. Pass-Key works (inasmuch as it ever worked) by preventing the starter enable relay from being grounded (so the starter won't turn), and disabling the command to the PCM that would enable the fuel delivery system (so the engine gets no fuel).

4) Plugs drenched with fuel = you got no spark

5) smell of paint after cranking = something plastic or painted is getting hot. Real hot. See if you can locate the smell. My guess is let's take a second look at coil pack. I wonder if your ICM has an issue or if the wiring to it became damaged and now has a short, or if the ground is badly corroded. There is a remote chance the Pass-Key module has gone bad (is that what's giving off paint smell?)

I am not certain what is in the start circuit that'd heat up on starting. You sure this car has never ahd an aftermarket starter/alarm connected?

Albertj

Thanks for the info, I am going to check out that Car Code software. My scan tool has a monitor mode, but only does basic sensors like O2, temp, etc.

AFAIK there is no after market alarm in this car. The original problem before it completly died on the PO was it would at random after driving it, not restart after you shut it off. It would have to sit for about and hour, then start and be fine. It stopped starting altogether and then I bought it.

moldymac wrote:

Thanks for the info, I am going to check out that Car Code software. My scan tool has a monitor mode, but only does basic sensors like O2, temp, etc.

AFAIK there is no after market alarm in this car. The original problem before it completly died on the PO was it would at random after driving it, not restart after you shut it off. It would have to sit for about and hour, then start and be fine. It stopped starting altogether and then I bought it.

It's highly highly likely that problem is the crank sensor. When they go bad they go "bad warm" first. the WORST part is that as they are going bad they work when cold. It is almost like they were intentionally designed to frustrate the car's owner and compel them to trade the car in. Which is probably a major factor in why the previous owner of your Riv sold it.

Regarding your exact problem, my car did this twice

The first time, after it had quit warm on me several times and I could not restart it, I had it towed in. The frst tow-in they replaced the fuel pump (admittedly it had cecome weak with age); after a while it started quitting again, but that second time they could not duplicate the problem so they sent me home so to speak. Third tow-in they still could not duplicate the problem and I told them to replace the crank sensor, "customer request." Reason: I did an internet search and found out that it's about the only problem you can have with this engine that *won't* set a code. They put in a cheap one (Standard T-series) that worked fine but quit about 2 1/2 years later - it dies on me twice. First time, could not find a problem. Second time, they simply replaced the crank sensor with a Delphi (I did not have to ask/tell them to do so). I later followed up with the dealer parts counterman (I was curious about it), who unofficially told me they'd had longevity problems with everyone's "economy" sensors on customers' and the mechanics' own vehicles.

Anyway... If you can, consider pulling the harmonic balancer and replacing the crank sensor. If there are any tears or cracks in the rubber in the balancer, replace it BUT be sure to use a good one. RockAuto shows 'em for about $80, I'd use the Dorman. GMPD shows them for $110. P/N was 12371986 (rockauto for '98) or 24507560 (parts fiche for SC 96-99), now seems to be 12563268 (this comes up on on GMPD and Monsterpartsonline says Part number 24507560 was superseded by part number 12563268" for 3800 SC engines '96 through 2004.). Sensor is Delco 213-151 or GM 10456161, $42 on Monster, $37 on RockAuto. Whatever You Do, Don't Cheap Out On The Crank Sensor or you will be sorry in 1-2 years.

If you can't DIY, it'd be a good bet to simply tow the car to a mechanic or dealer and have the cranksensor replaced. I am told dealers have a special puller. Job should come in just over $120.00 all in. DIY, $50 assuming you already have a balancer puller $100 if you don't -- a common puller will work but be careful not to tear the rubber inside the balancer.

Let us know what you do!

Albertj

I was thinking either the crank or cam sensor, just from experience from my 87 lesabre with a 3.8. The sensor isn't that expensive, I think I will just replace it. Shouldn't be too bad compared to the engine swap I did on my other Riv

IIRC bad cam sensor won't keep you from starting (ecu can reckon0 but will give you worse gas mileage and other drivability issues. Bad cam sensor leaves you inop.

So hey' I'm not a mechanic and I'm not under the hood of your car, so take it all with a grain of salt. But FWIW I strongly suspect crank sensor based on the failure pattern you describe.

Albertj

To those who guessed crank sensor, you got it! Bought a delco one from rock auto, put it in, and she fired right up. Ran like crap for a few and kept stalling, but after feathering the gas for a bit it ran fine. Must have been missing on some cylinders being that the plugs were probably still drenched in gas. But it runs great, took her for a ride on the high way and it ran excellent. Thanks guys!

moldymac wrote:

To those who guessed crank sensor, you got it! Bought a delco one from rock auto, put it in, and she fired right up. Ran like crap for a few and kept stalling, but after feathering the gas for a bit it ran fine. Must have been missing on some cylinders being that the plugs were probably still drenched in gas. But it runs great, took her for a ride on the high way and it ran excellent. Thanks guys!

U R welcome, but don't get frustrated with coincident problems when they crop up. For instance, your ignition switch might quit soon, it has a similar but not identical failure pattern.

Albertj.

this is just an update from this post I made a long while back...

the mom and pop gas station is gone...I think they had too much crap in their new new fuel tanks at the pumps...and it messed up more than my car... they only sold gas for like a week or two, then they covered the pump nozzles...after about 6 months the whole place is shut down... crappy gas will put you out of business!

Eldo wrote:

Natesriv wrote:

I read about a post regarding steering shudder and a tsb...I think I may investigate that.

Here's the TSB. I will note that my '97, which is only supposed to need a new pressure hose, was not cured by replacing the pressure hose...

Steering Vibration/Shudder During Parking Manuever (Install Power Strg Pressure Hose Assm) #99-02-32-007A - (Jan 31, 2001)
Steering Vibration/Shudder/Moan During Parking Maneuvers on Dry Pavement (Install Power Steering Pressure (Inlet) and/or Return (Outlet) Hose Assembly)

1995-99 Buick Riviera

1997-2001 Buick Park Avenue, Ultra

2000-2001 Buick LeSabre

2000-2001 Pontiac Bonneville

This bulletin is being revised to add the 2001 model year and to update the parts information. Please discard Corporate Bulletin Number 99-02-32-007 (Section 2 -- Steering)
Condition

Some customers may comment on a steering vibration, shudder or moan noise when steering during parking maneuvers on dry pavement.
Correction

Install a new power steering pressure (inlet) hose assembly on the following vehicles:

* 1995-98 Buick Riviera
* 1997-98 Buick Park Avenue and Ultra

Install a new power steering pressure (inlet) and return (outlet) hose assembly on the following vehicles:

* 1999 Buick Riviera
* 1999-2001 Buick Park Avenue and Ultra
* 2000-2001 Buick LeSabre
* 2000-2001 Pontiac Bonneville

Diagnosis

Important

In diagnosing the above listed vehicles, do not overlook other obvious repairs prior to replacing the hose(s).

1. Verify that the power steering pump reservoir is full.
* If fluid level is low, fill and check for leaks.
* If power steering system has air in the system, perform the "Bleeding Air from Power Steering System" procedure as described in the Power Steering System sub-section of the Service Manual.

Important

When performing the "Bleeding Air from Power Steering System" procedure, it is important that the front of the vehicle is supported by the lower control arms. If the vehicle is not supported by the lower control arms, the procedure may cause the strut bushing to dislocate and cause new concern.
2. Verify that the accessory drive belt is in good condition and that the pulleys are not bent or damaged.
3. Verify proper belt tension and operation of the belt tensioner.
4. Check for power steering hose ground out conditions.
5. Check for good engine idle and correct engine RPM.
6. Check to see that the rear transaxle mount does not have a plastic assembly aid installed which is used for assembly purposes. If the assembly aid is installed, remove the assembly aid and install the rear transaxle mount.
7. With the vehicle on dry pavement, maneuver the vehicle in parking positions. If the steering vibrates/shudders or moans in this test, replace the power steering pressure hose and/or the harmonic balancer.

Important

A defective harmonic balancer on the 1995 Buick Riviera can influence steering vibrations after power steering hose installation.

Important

When installing the pressure hose on the 1995 Buick Riviera, pull down on the pressure hose at the rear of the engine or bend the hose to allow clearance between the hose and the front of the dash.

Power Steering Pressure (Inlet) Hose Replacement Procedure

For 1995-1998 Vehicles:

1. Raise and suitably support the vehicle.
2. Refer to Vehicle Lifting and Jacking in the General Information section of the Service Manual. Drain the power steering fluid.
Refer to Draining the Power Steering System in the Power Steering section of the Service Manual.

3. Remove the power steering gear assembly heat shield.
4. Disconnect the power steering pressure hose from the power steering pump assembly.
5. Remove the bolt/screws from the retaining clips.
6. Disconnect the power steering pressure hose from the power steering gear assembly.
7. Remove the power steering pressure hose assembly from the vehicle.
8. Install the power steering pressure hose assembly to the vehicle.
9. Connect the power steering pressure hose to the power steering pump assembly.
10. Connect the power steering pressure hose to the power steering gear assembly.
Tighten the power steering pressure hose to the steering gear to 27 N·m (20 lb ft).
11. Install the bolt/screws to the retaining clips (3).
Tighten the retaining clip bolt/screws to 6 N·m (53 lb in).
12. Install the power steering gear assembly heat shield.
13. Lower the vehicle.
14. Fill and bleed the power steering system using, J 43485.
Refer to Corporate Bulletin Number 83-32-09, dated November, 1998.
------------------------------------------------------------------------------------------------

Power Steering Pressure (Inlet) and Return (Outlet) Hose Replacement Procedure
[NOTE: On these vehicles, the new Return Hose runs around the whole engine compartment, rather than up & back on only the passenger side.]

For 1999-2001 Vehicles:

1. Raise and suitably support the vehicle.
2. Refer to Vehicle Lifting and Jacking in the General Information section of the Service Manual. Drain the power steering fluid. Refer to Draining the Power Steering System in the Power Steering section of the Service Manual.
3. Remove the LH front wheel/tire assembly.
4. Remove the LH lower splash shield.
5. Remove the lower radiator air deflector (engine splash shield, if installed.)
6. Remove the power steering gear assembly heat shield.
7. Disconnect the power steering pressure hose and the return hose from the power steering pump assembly.
8. Remove the bolt/screws from the retaining clips.
9. Disconnect the power steering pressure hose and the return hose from the power steering gear assembly.
10. Remove the power steering pressure and return hose assemblies from the vehicle.

11. Drill two 6 mm (¼ in) holes into the top surface of the LH engine frame longitudinal crossmember for the new return hose clips.
12. Both holes are to be approximately 35 mm (1.5 in) rearward from the front and rear control arm brackets horizontal flange edge. Remove the two rosebud clips from the new hose assembly.
13. Install the two rosebud clips into the holes drilled.
14. Install the new LH-routed power steering return/outlet hose assembly:

* From the forward side of the front engine mount, route the pump end of the hose assembly to the RH side of the vehicle, along the RH engine frame crossmember and up to the steering pump assembly.

* Route the steering gear end of the hose assembly to the LH side of the vehicle, rearward along the LH engine frame crossmember and up to the steering gear assembly.

15. Install the power steering pressure/inlet hose assembly to the vehicle.
16. Connect the power steering pressure and return hoses to the power steering pump assembly.
17. Connect the power steering pressure and return hoses to the power steering gear assembly.
Tighten the power steering pressure and return hoses to the steering gear to 27 N·m (20 lb ft).
18. Install the bolt/screws to the retaining clips (5).
Tighten the retaining clip bolt/screws to 6 N·m (53 lb in).
19. Install the power steering gear assembly heat shield.
20. Install the lower radiator air deflector (engine splash shield).
21. Install the LH lower splash shield.
22. Install the LH front wheel/tire assembly.
23. Lower the vehicle.
24. Fill and bleed the power steering system, using J 43485.
Refer to Corporate Bulletin Number 83-32-09, dated November, 1998.


Parts Information


1995-98 Buick Riviera
1997-98 Buick Park Ave & Ultra

26059162 Power Steering Pressure/Inlet Hyd Hose Assembly (with Magna Steer)

1997-98 Buick Park Ave Ultra

26060025 Power Steering Pressure/Inlet Hyd Hose Assembly (w/o Magna Steer)

1999 Buick Riviera
1999-2001 Buick Park Ave & Ultra
2000-2001 Buick LeSabre
2000-2001 Pontiac Bonneville

26079289 Power Steering Pressure/Inlet Hyd Hose Assembly (with Magna Steer)

1999 Buick Riviera
1999-2001 Buick Park Ave & Ultra
2000-2001 Buick LeSabre
2000-2001 Pontiac Bonneville

25727230 Power Steering Return/Outlet Hyd Hose Assembly (with Magna Steer)

This is good info. Not sure why I missed it before. My car was making a decent shuddering/groaning sound on slow turns in parking lots and onto streets. Replaced tie rod ends and that condition went away almost entirely. Still there a tiny bit so I'm guessing the TSB above holds true.

Oh and Nate, I'm surprised the gas station didn't have filters on their pumps to prevent their patrons from getting their own auto fuel systems gummed up. Odd... At least they aren't screwing up people's vehicles anymore. lol

that station is now boarded up and gone... They were open for awhile while they weren't selling any more gas...now it's all gone...

When I try to start it theirs this longated beep noise followed by several short beeps, what could be wrong?

DarkVader wrote:

When I try to start it theirs this longated beep noise followed by several short beeps, what could be wrong?

no idea, especially since riv's warning is a chime not a beep.

GUESSES:

- if you have an aftermarket alarm/immobilizer, remove it or go to the installer and have them fix it.

- check your battery voltage (car off, disconnect negative lead and test with voltmeter) and if it's below about 12.4 volts (while disconnected) that may help point to the problem.

let us know

Albertj

Thanks

Hey,

First off, I've been a lurker for a long time and have learned (and applied) a ton of stuff from this forum, so here's a belated thanks! But I finally had to break down and register because I have a new problem that I need help with ASAP.

Briefly, I have a supercharged '95 Riviera that I love, it has 140K on the chassis but much less on the engine as it was replaced within the last 10-15K miles or so. I don't have my records in front of me for exact details. All was fine after the engine, then it was off the road and sat in my driveway for about a year with a bad alternator, shot rear shocks and a faulty leveling compressor. Thanks to you all, I finally got around to pulling the compressor and replacing the shocks and the alternator, then had my mechanic give it the once over to get it back on the road. I don't have the specifics in front of me, but it didn't take much more than plugs at the garage as I recall.

Fast forward to last week - it ran like a top for about 1000 miles, except for a very occasional sputter when the engine was under load and at around 3000 rpm/30 mph. Never had a Check Engine light. I planned to have that checked but didn't get to it in time, and it may or may not be related to what happened next. I drove to the in-laws without a problem, parked, and when I came out to leave the engine turned over and ran for about 1 second, then stalled. From that point, it cranked but wouldn't start, no matter how long I let it set. It seemed like it was out of gas (which it wasn't) or a bad fuel pump. Fuel pump is around 5 years old BTW.

Had it towed to my mechanic who has always been great, but long story short, he can't find it. It's not fuel-related, and after spending a day diagnosing signals and such, he found that not all the cylinders were firing and there was a sensor error that led him to believe the cam and crankshaft were out of sync. He decided the timing chain must've jumped, in fact he concluded that was the only possible explanation. I was a little skeptical because the engine wasn't that old and I can't imagine they didn't replace the chain at the same time, but it also sat idle for a year, so what do I know? I gave him the go ahead to rip it down and, you guessed it, that's not the problem.

He tried a few more things, like replacing the sensor (not sure which, I'm trying to recall all this from a 3 minute phone call) and a new "computer" by which I assume he meant ECM, but no luck. He's about 99% of the way to having me dump it on the dealer, which after all this may break the bank. It's already costing me cubic dollars at this point, so starting over at the dealer will be crushing. He's waiting on a call from his "GM guy," so I have my fingers crossed, but I thought if I could get some ideas from this forum of things that I could tell him to check, it might head off the need to get it to the dealer.

I read a whole lot about problems with the sensor magnet, a lot about wiring issues that were causing similar problems, even the need to do a CASE learn when the ECM is swapped out, but some of these were Series II-specific so I don't know if they apply to me. If it means anything, some posts mentioned weird behavior with the traction and/or security dash light, and I think I may have seen that on occasion.

Sorry for the sketchy details, but if anyone has any ideas or can suggest questions I should be asking, I can get them answered when I speak to the garage tomorrow. Please help! Thanks!