I have 1998 old regency starts up when engine cold but after engine get hot it wont start back up untill cooled off & shows low fuel pressure coming from fuel pump?

check fuel pressure make sure they are within specs. then if it is , very possible that you a problem with ignition module. this module is known to fail, and my experience using rebuilt is not good it took 6 unit before we got a good one. good luck

1998



1.6L or the 1.8L

good pressure. no melted cat.

so what engine,, (but both are MAF based systems)soooooo

low power, all the time. lits call it bogs. (3letters)

elaborate that, when does power end.

hot , cold both engine temp?

only tip-in BOG... you move foot fast , it bogs then catches up.?

or you TIP-in and its bog city all the way to WOT. ( wide open throttle)



when was the last time car was DD, a daily driver.

last week ,month or decade? key question.

bad fuel of over 6months old fuel?



here are the tests.

1: all fuses good. (always for ever and ever)

2: key on,

3: the dash lights up , oil, charge, and CEL, is the CEL on, it must be.

4: start car, CEL goes out , does it, stay out running???????

5: bogs, hot ,or cold engine block?

6: no codes, does that mean an OBD2 scan tool shows no DTCs stored, and no pendings, and all monitors complete, no it wont

with the CAT gutted,, it will show P0420x for ever. bad dead cat.



what does no code mean.

here is a oBD2 1996 scan of the G16b ENGINE,

the J18 engine would do same......

http://www.fixkick.com/ECU/Authority/A_Full_OBD2_scan.html



see the tests. here.



bogging with either engine, hard lasting hot bogging, is:

in no order... fate is random , in many cases...

1: low fuel pressure, (not you) stated for full correct.

2: clogged injectors.

3: bad fuel.

4: weak maf, ECU cant tell weak , only dead. or just a dirty maf. ask.!



one way to prove a WEAK maf, is to unplug it

the ECU then see that and creates a virtual simulated MAF.

it will not have full power, but will have lots.

it will run in suzuki limphome mode, with retarded timing, and low power and limted RPM.

it will suck fuel.

i never do it because i have the outputs logged. i use a voltmeter



http://www.fixkick.com/sensors/92-95MAF/92-95-MAF-testing.html

have a fuel pressure test done to check the pump, pressure regulator and filter. It may be getting a vapour lock from low fuel pressure.

What is the fuel pressure when the engine is running ?
Has the filter been replaced ?

How long since overall tune-up? Use a gage and check proper fuel pressure, key on engine off. vin K 48--55 psi. Also, check that the fuel pressure will hold for bit, with the key off.
Check fuel trims when problem is ongoing, see if trying to add or remove fuel? If temp related check the coolant temp sensor.
Over-fueling on a hot engine can make it hard to start. Pushing the pedal to the floor should put it in "clear flood mode" and help it to start.
Could be other issues?

Is the gas tank above 1/2 tank now?

A worn / aged fuel pump will fail when it's hot and the fuel level is low (example: below 1/4)

Park your car in a cool area.

Start the car when it's cold outside,

===
Check the engine fuel pump pressure.
===
Replace the fuel pump relay,fuel filter,fuel pump and fuel pump stainer at the same time.
===

You need 3 things.
Compression
Good hot blue spark to all plugs.
Good gasoline and proper fuel pressure. 63-64 lbs.
If you have all 3 then move on to injector pulse to all injectors.
I think each injector is on a separate driver on that one.
Check for pulse to all of them.

You may be weak on fuel pressure . Even a couple of lbs low on a cold start will cause a no start. Double check cold start cranking fuel pressure. If under 63-62 lbs you have problems.one test is to give it a squirt of carb cleaner not starting fluid. If you get a intake or engine full of starting fluid it can blow things. Carb cleaner will start it if it is a fuel problem and lot safer. Also in the good old days when i was a kid, i used to get a couple of cans of starting fluid and get in the back and have a good starting fluid spraying contest. Good for a big blast if someone lights a match. If it starts then you have a fuel pressure problem. Run the full fuel pressure test and post back pressures.

Here is the guide lines on testing.
Hard to start cold.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel. Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.

The 75-85 is only a check on the capable full pressure of fuel pump.
If you can not find the rubber return line check full pressure by plugging return line or just or the true full pressure can be taken direct at the end fuel filter.
What are the pressure readings that you have done.
What are your cold start pressure readings?

You need 3 things.
Compression
Good hot blue spark to all plugs.
Good gasoline and proper fuel pressure. 63-64 lbs.
If you have all 3 then move on to injector pulse to all injectors.
I think each injector is on a separate driver on that one.
Check for pulse to all of them.

You may be weak on fuel pressure . even a couple of lbs low on a cold start will cause a no start.
Double check cold start cranking fuel pressure. If under 63-62 lbs you have problems.
one test is to give it a squirt of carb cleaner not starting fluid. If it starts then you have a fuel pressure problem.
Run the full fuel pressure test and post back pressures.
Here is the guide lines on testing.
Hard to start cold.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.

The 75-85 is only a check on the capable full pressure of fuel pump.
If you can not find the rubber return line check full pressure by plugging return line or just or the true full pressure can be taken direct at the end fuel filter.
What are the pressure readings that you have done.
What are your cold start pressure readings?
Post back what you have.

The other thing to that is common is the (ICM) under the distributor cap. There is a breather screen on the bottom of the distributor that get's clogged with dirt causing condensation promoting corrosion, this was gm TSB for replacing the cap and rotor to make sure it's clean.

Good luck and hope this helps. Merry Xmas.

Has Neon do same, I ran fuel at low level, on hot day, ran engine until it started to act up & threw a fuel pressure gauge on it. Was at approx 5 psi. Cold next morning, 48-50 psi. Always hot day about 30-40 miles into work in morning, o.k. Sit in hot sun all day & would happen 3-4 times on way home. Sit and let cool, 20 minutes or so & go again for a while. Cool day, no problem. Change pump I would.

WHAT TROUBLE CODES DO U HAVE