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We had to change the distributor in my 1997 Chevy Tahoe 5.7 4wd. After putting the distributor in my truck, we used the scanner to do the cam retard. But my truck will not start on its own! We have to put gas into the throttle body in order to start it! Once started, it idles fine, but when I put it in gear and push on the gas pedal, it dies. What do I need to do, to get the initial gas into the motor for it to start? And how do I keep it running after putting it in gear?
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Suggest you start with check your fuel pressure at the rail.
From what your stating it appears yours is low.We did check fuel pressure. It said it was 55?? I don’t know what it is supposed to be!
But if the fuel pressure was low, wouldn’t it prevent it from idling as well?
When I talked to my husband on the phone, he said that we should hear the injectors come on real quick if we turned the distributor. We don’t hear anything!!
Could it be the camshaft sensor? How do I check that thing to see if that is bad? Cause I have the one that was off my original distributor as well as the one on the distributor from picknpull!Thanks
If the cam sensor was preventing the engine from starting..
Putting fuel in the intake would make no difference.
But you say after putting fuel in the throttle body the engine will start and run
I still believe you have some sort of fuel delivery issue.
If it is a cam sensor you’ll need a good diagnostic tool or a scope setup to see if your getting a cam signal.The codes that pull up now are P0300 – Engine misfire detected
and P1345 – CKP/CMP Correlation Problem.I don’t know what the P1345 means at all!
The Crankshaft Position (CKP) sensor is a permanent magnet generator, known as a variable reluctance sensor. The magnetic field of the sensor is altered by a crankshaft mounted reluctor wheel that has seven machined slots, 6 of which are equally spaced 60 degrees apart. The seventh slot is spaced 10 degrees after one of the 60 degree slots. The CKP sensor produces seven pulses for each revolution of the crankshaft. The pulse from the 10 degree slot is known as the sync pulse. The sync pulse is used to synchronize the coil firing sequence with the crankshaft position. The CKP sensor is connected to the powertrain control module (PCM) by a signal circuit and a low reference circuit. The Camshaft Position (CMP) sensor is triggered by a notched reluctor wheel built into the exhaust camshaft sprocket. The CMP sensor provides 6 signal pulses every camshaft revolution. Each notch, or feature of the reluctor wheel is of a different size for individual cylinder identification. This means the CMP and crankshaft position (CKP) signals are pulse width encoded to enable the powertrain control module (PCM) to constantly monitor their relationship. This relationship is used to determine camshaft actuator position and control its phasing at the correct value. The PCM also uses this signal to identify the compression stroke of each cylinder, and for sequential fuel injection. The CMP sensor is connected to the PCM by a 12-volt, low reference, and signal circuit.
That is the technical explanation.
You may have an issue with the following:
Distributor was installed incorrectly.
Distributor timing is not set correctly
Not 100% sure if a CKP/CMP Correlation relearn is needed on your vehicle.
Timing chain stretched / worn.So, none of my problems would be because of the map sensor, right? Because that was what we were gonna go buy next!
Oh, how would i do a relearn?
When the rain stops, we will go check the distributor, timing, and timing chain!So, none of my problems would be because of the map sensor, right? Because that was what we were gonna go buy next!
Not according to the code you listed.Oh, how would i do a relearn?
When the rain stops, we will go check the distributor, timing, and timing chain!
Before a relearn, you need to determine if the distributor is aligned and timed correctly.
How much ( if any ) the timing chain is stretched or worn and might need replacing.
Then you will need to check what the actual CKP/CMP Correlation is with a scan tool or scope.
Again, I do not know for certain if your vehicle requires a relearn procedure but it can be done through a professional scan tool.
Pretty much all the information concerning this can be found on youtube.I don’t have much experience with domestic vehicles, BUT I do know that this thing has spider injection. If the injectors aren’t perfectly timed with the distributor, you’ll get all kinds of timing codes and crank no starts.
Okay, so I had my stepson come mess with my truck for me. From what he could deduce, he said he wants me to check the fuel pressure again, in which I did tonight. With the key on, no start… the fuel pressure tops out at 48 and starts dropping back down to zero. When we started the truck, (by putting gas in the throttle body), the fuel pressure holds steady at 48. And when we didn’t put gas in the throttle body and tried to start it (it won’t start unless I put gas in the throttle body), it will hold steady at 48 as it tries to start!!
So, would that be a fuel pump issue, or a fuel pressure regulator issue??
In the morning, I’m going to go to pick n pull and get as many crankshaft sensors, map sensors, knock sensors, and o2 sensors as I can find!! And we will replace and try to rule out those as part of the problem hopefully!!
Is there anything else I should go look for while I’m out at pick n pull?Thank You!!
Being that you have fuel pressure but the engine will only fire off when you add fuel to through the throttle body.
It would appear your injectors are not supplying fuel.
The issue may be what is controlling the spider injector unit if the vehicle was running before.One of your injectors could be leaking too. I’d suggest removing the spark plugs, then turn the key to the one position (key on engine off), and check if there is fuel squirting into the cylinder.
Have you tried starting the truck while someone slowly rotates the distributor +- 15 degrees? I know you guys got the base timing set, but you’re popping a code telling you that the base timing is wrong.
97-99.3 SBC’s are the odd one because GM did not put timing marks on the crank pulley. If there is any slack in your timing chain or the distributor is more than +-2 degrees off, starting becomes a real nightmare.
Rotating the distributor will at least get you close enough to start the engine at which time the computer can take over and adjust the timing for you. BTW, your fuel injection system is heavily reliant on correct cam to crank timing in order to know when to open the injectors.
I would try rotating the distributor first. If the computer can get the engine started and maintain a half-way decent idle, you can instantly rule out a lot of other things.
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