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Hi there. If you start the vehicle, and bring the rpms up a bit while holding the brake can you put the vehicle in drive without it cutting off?
I did try that a couple of times. the first time it worked but not the next time. I also tried doing it with a/c on, to bring the idle speed up.. It caught, then stumbled and died.
from where? It starts and runs smooth and runs great at speed and dies at idle, but starts and runs smooth with a shot of starting fluid. give me some other tests to check. Are you a cadillac catera expert or general mechanic. I think i need an expert as the catera is different . no Chilton or Haynes manuals on it.
This is Eric.
Please remember that I cannot bee there to see, hear, feel, or otherwise check anything myself, so i have to rely on you to be as specific as possible, and I may need to frequently ask for more information or ask for you to perform certain tests.
Do you have a fuel pressure gauge, digital voltmeter, diagnostic scanner with live data, freeze frame, and testing capabilities?
Was an aftermarket or factory Fuel pump used?
If you know the last active engine fault codes that were retreived, please list them as they may in fact be pertinent to your problems
Thanks, Eric. I do have a voltmeter and fuel pressure tester, but no scanner. I cannot find the location of the test schrader for the fuel. I loosened the fitting to the fuel rail and it squirted out. I had a friend quickly cycle the ign, switch and plenty of fuel is available. I don't have current trouble codes because I can't get it to run long enough to get to an auto zone. I will tomorrow if I have to carry it on my back! I did get them about 3 weeks ago. no #'s but 4 statements. They relate to the traction control, abs, and speedo problems. 1. electrical connection or short circuit. 2. failed vehicle speed sensor. 3. drive gear mechanical fault. 4. failed cvt unit. nothing about dying at a stop light.
I was pretty detailed on my checks in my questions. The mysterious thing is how well and powerfully it runs down the road and how smooth it idles in park and dies when put into drive and won't restart until primed with starting fluid. I f only they made a Chilton or someone, it would sure help. Maybe you can connect the dots.
Already done since August. o2 sensor, maf, fuel system check, and a new fuel filter last week.
Looking forward to your expertise. Any additional info, I'll get for you.
Ok, the first test will be for proper fuel pressure. Key On Engine Off pressure should be 40-46psi.
Valve should be located right at where fuel feed and return lines junction at the fuel rail- :
Attachments are only available to registered users.
The fuel pressure shoud stabilize within a second or two of the fuel pump stop running. Watch pressure, it should not drop more than 5psi in first 10 minutes.
If pressure holds, relieve fuel pressure to 10psi. At that point pressure should not drop more than 2psi in 10 minutes.
If you have an autozone nearby, they normally rent out a code reader- get deposit back when you return it.
Let me know the results of the tests, and we will go from there. I want to rule out fuel related before jumping into the PCM(powertrain control module).
Just wanted to let you know I will be off-line shortly for the evening, but will be back in the am and on until about same time
I rented the code reader at Autozone and did the fuel pressure test too. I had to remove the air plenum to reach the schrader. Well hidden. Pressure jumped to 40# and was rock solid for 10 min. Bled down to 10# and it stayed there for 10 min. I was able to keep fitting on and got plenum on. Pressure with engine on was 48# including shutdown of engine after running 11 min. with water temp. about 1/2 scale.
When I drove up to Autozone this morning about 2miles keeping my foot on throttle about 1000 rpm, engine did'nt shut down. When I went to leave, engine would'nt start until I gave it a dose of starting fluid. I drove home tickling the throttle. As soon as I let off throttle, it died.
Read codes at this time: 1of6 P1700 manufacturer control transmission
2of6 U2108 manufacturer specific DTC(see service manual)
3of6 P0500 vehicle spd sensor A malfunction
4of6 U2108 (same as 2of6)
5of6 P0727 engine spd sensor circuit no signal-pending
6of6 P0335 crankshaft position sensor A circuit malfunction
Erased codes. U2108 remained. Had to erase separately. Turned ign. switch to on and code U2108 came back on.
Just tested again. Needed starting fluid to start 1st time.Engine ran great. Went to fast idle 'til warmed up (about 1000rpm) then settled at 500rpm. Ran 12 min. and shut down.
Read codes: 1of3 U2108
2of3 P0727 engine spd sensor circuit no signal- pending
3of3 P0335 crankshaft position sensor circuit malfunction-pending
Where do we go from here? Anymore tests? A new crankshaft position sensor is $56.49 at NAPA. Should I try that? Before the last test, I changed the plugs and rechecked all vacuum lines and electrical connectors.
The crank sensor is probably going to be part of it. but let me check on the manufacturer's codes you are showing- these may give us a clue on the communication of the computer. I will either post back in awhile or first thing in the morning.
Before having you do any other tests or buy any parts I need to go thru all this and see what direction it is leading us in- please be patient for just a little bit longer and we will get your Catera going
Please remember, you have already accepted an answer, so further accepts are not required. I just want to help get you going
Thanks a bunch. I feel a lot better with your expertise. I've got patience and trust that that little car will run......ah, I mean KEEP running!!
Have a great week.
Ok, DTC U2108 is the ECM losing communication with the EBCM(electronic brake control module)-the abs system. The only tests are with a factory scan tool, but 9 times out of ten it is due to a faulty EBCM. That is why you have ABS and Traction Control lights on-
Now, back to the main problem at hand. Below are tests to run for CKP sensor fault code- DVOM is needed:
Here's the bad part, if either CKP sensor or ECM is bad, aftey they are replaced, a diagnostic scanner with programming caabilities is required to program either thru arelearn procedure.
But before we get to there, let's see what the tests show.
I was concerned about leakdown of fuel pressure, but that tested good- one thing eliminated.
The non-working speedo is the vehicle speed sensor.
The trans code P727 - engine speed sensor circuit no signal may have been caused by the loss of signal when engine cut out, so we wont worry about that until engine is running right.
When you get some results from the above tests let me know and we will go from there.