Car is hard to start.

bob k · #1 (**permalink**) 05-12-07, 03:07 PM

For a while now the car is getting harder and harder to start. It always seemed to have difficulty starting up since we got it, but lately it has gone really bad. You hold the key, it turns, but it wont catch for a good 3 seconds. Sometimes I have to attempt to start the car 3 or 4 times before it finally fires up. When the engine is hot it is fine. Otherwise its hard to start when cold or even if it is rainy outside.

Plugs and wires are relatively new, they were changed over a year ago and only have several thousand miles on them. Then this past early spring (I think January-Febuary-ish) we cleaned a very dirty throttle body (it looked like a rocky cave in there!). It helped with this problem for a short while, and it had improved the car with throttle response, but my dad is the primary driver, and after that time when we cleaned the TB, it just got back to its hard starting routine all over again. In very recent months its just a bitch to start her up.

So what should I be looking at here? Thank you for your help.

carnut · #2 (**permalink**) 05-12-07, 04:14 PM

If I understand you correctly, it cranks too long before it fires up? If thats the case I would have the fuel pressure and rest pressure confirmed to be at spec. Rest pressure is fuel remaining in the fuel lines for a specific time and at a specific pressure. Fuel injected engines require fuel to be present in the fuel line under pressure to anticipate the next engine start. If rest pressure falls below spec, you have to crank the engine too long to refill the lines and restore pressure. Rest pressure and fuel pressure are controlled by the fuel pump within the fuel tank and check valves in the fuel return system to the tank. Diagnosis is very important. Verify, verify, verify these two pressure readings and report back.

**Ranger** · #3 (**permalink**) 05-12-07, 05:21 PM

Also check the fuel pump relay. If it is bad, the engine must build enough oil pressure via cranking to override the relay and enable the fuel pump.

Additionally, while the FPR usually causes difficult HOT starts, it is easy enough to check.

chubbyranger · #4 (**permalink**) 05-12-07, 05:29 PM

Can you also use the duration of the fuel pump run pre-start as an indicator? Turn the key to "on" and listen to how long the fuel pump runs. If its a fuel pressure problem wouldn't it run longer than normal? And therefore if you wait for the fuel pump to stop before cranking the engine you should have enough fuel pressure to light it up? Another possibility if you cleaned the throttle body after changing plugs could some of the loose crap foul the plugs? Never dealt with this before so I'm just pulling this out of my chubby butt.

**Ranger** · #5 (**permalink**) 05-12-07, 05:50 PM

Quote:

Can you also use the duration of the fuel pump run pre-start as an indicator?

No, if cranking is not initiated within 2 seconds after key on, the pump shuts off til the engine is cranked.

Gearheaad43 · #6 (**permalink**) 05-12-07, 07:42 PM

I would look to see if you got any codes ..... Start suspecting a BAD ICM, FPR, coils, or FP.you can test the Fuel pressure to eliminate a bad FP or FPR, then that leaves the IMC coils, or CKP suspect.

71CHALLENGER · #7 (**permalink**) 05-13-07, 12:28 PM

Does the car also sometimes stall when driving? Even for the slightest amount of time?(stall and then keep running) Best to check if there is any codes before guessing. My 97 eldo and probly others have a way to retrieve the codes without a scanner by using the heater controls to access them. when mine was hard to start and it would intermittently stall, I pulled up a 1599 code. After putting a fuel pressure guage on the car when it was hard starting, It showed the pressure as normal. I replaced both crankcase position sensors(not too difficult) and problem solved. It seems these (Eldo's) had problems with these.

bob k · #8 (**permalink**) 05-13-07, 12:35 PM

No stalling problems. Ill see if I can pull some codes. Do you have directions on using the heater controlls for pulling codes?

Ill inform my dad and he will probably do a pressure test when he goes to work on Monday.

chubbyranger · #9 (**permalink**) 05-13-07, 01:54 PM

Quote:

Originally Posted by bob k

No stalling problems. Ill see if I can pull some codes. Do you have directions on using the heater controlls for pulling codes?

Ill inform my dad and he will probably do a pressure test when he goes to work on Monday.

On earlier Cadillacs you press and hold OFF and WARMER with the key On. Engine can be running or not. I don't know your car well enough to know if that's how you do it. Check the Tech Tips section on this site and you should find instructions for your car.

z06bigbird · #10 (**permalink**) 05-13-07, 08:00 PM

Extended crank. Ask your Caddy mechanic. He will need to put it on scope. If not any of the above, switch to brand name gasoline.

**Ranger** · #11 (**permalink**) 05-13-07, 11:02 PM

I think the '97 Seville might be the OFF & PASSENGER WARMER buttons.

bob k · #12 (**permalink**) 05-15-07, 06:10 PM

Do you have instructions on how to test fuel pressure? Chiltons is crap, im just about ready to throw out this book.

Edit: Ive managed to pull some codes, and according to the PCM it says I have issues:

PCM P0603 - History - Control Module Long Term Memory Reset
PZM B0533 - Current - Fuel Sensor Open/Shorted To B+
PZM B2471 - History - Interior Lamp Fault
PZM B2477 - History - Reverse Lamp Relay Shorted to Ground

Another update: Car started fine today. Both in the morning before going to work and before coming home. My dad had helped to jump someone yesterday before leaving from work, and since then the car started fine. I have a sneaky suspicion that it could be the battery contacts. Im going to give them a thorough cleaning and see if the problem goes away for good. I have experienced strange stuff from cars in the past due to dirty battery contacts, and the codes listed above definitely looks like a battery contact issue since none of them make sense except possibly the fuel sensor, since my lamps are fine, and I haven't disconnected the battery in months.

carnut · #13 (**permalink**) 05-15-07, 09:24 PM

As you can see the only code thats worth checking is the current one, fuel pressure circuit open. Clean the battery connections, verify all engine to chassis grounds are clean and tight and verify the wiring connector to the oil pressure sender is clean and secure. Erase all codes and check again in a week of use. History means sometime in the cars past 2 days or 2 years ago? (whenever) it had a problem. The problems were fixed and the codes were never erased.

**Ranger** · #14 (**permalink**) 05-15-07, 10:16 PM

Quote:

Chiltons is crap

We could have told you that.

A history code will clear itself after 50 ignition cycles with no failures detected.

Quote:

Do you have instructions on how to test fuel pressure?

Get a fuel pressure gauge. Remove the cap on the fuel pressure service port located on the fuel rail. Screw on the gauge and start the car. Read the gauge.