Broken bracket 1988 Chevrolet Silverado 5.7

This truck has an engine accessory bracket mounted to the front of the engine that holds the air pump, the compressor, the power steering pump and the alternator in position. That's a lot to ask of a questionable strength piece of metal so they were always prone to develop cracks. The mounting bolts to engine were also known to loosen and fall out over time. It wasn't unusual to find broken bolts and broken bracket.

This particular bracket had been repaired with a weld at one point but was now broken again just above the weld and a bit higher near one of the bolt holes.

I also had two broken bolts. One at mount hole A and one at mount hole B.

The bolt at hole A (did you think I was gonna say A-hole?) was broken off almost flush but just enough sticking out to get vise grips on it. The bolt at hole B was sticking out a couple inches but neither bolt would budge with the vise grip method. This was the time to use a good penetrating fluid on the threads. Don't get me wrong, I think WD-40 is great stuff and I use it a lot but the best thing I use in a situation like this is KANO Sili Kroil. Spray it on and let it soak. In this case I let it soak overnight. The next morning I was able to get the broken piece out of A with the vise grips. B was still stuck.

Heating didn't seem to be an option because the hole was very close to the intake manifold gasket.

Maybe a stud remover would give me a better grip and be enough to do the trick. With the stud remover and a 1/2 " breaker bar I did indeed get a better grip. Unfortunately that didn't help either.

If you have a full thread stud sticking out sometimes you can thread two nuts onto the stud, jam them together buy turning them against each other and then turn the inside nut to try and back the stud out. This broken bolt didn't have threads the full length though so I took a die and cut threads along the length of the broken bolt.

I had just gotten the threads cut and was searching for 3/8" SAE Coarse nuts when the Snap-on tool truck pulled in. In case this trick didn't work I thought it would be a good idea to see if he had a 3/8" bolt extractor, which he did. Those things can do wonders at times but I didn't have that size in the shop. The extractor though, whether it worked or not would damage my freshly cut threads so I bought the extractor as a next step if the two jammed nuts didn't work.

He also brought in a MSK10 Snap-on stud removal kit. I realized this was the jamming two nuts together idea but on steroids as the tool is designed exactly for that. Perfect timing and not a bad price. The broken bolt came out hard but it did come out. Appears to have been cross-threaded or wrong-threaded.

Now I just need to run a tap into these bolt holes and clean up the threads. The new bracket is here. All downhill now! I hope.

Thanks for reading!

Kenny@ggauto.repair

When it says low fuel it might be out of gas.

I had a 1999 4Runner towed in several days ago for a no-start condition. The engine cranked just fine. I sprayed starting fluid into the air filter and the engine started. What that told me was I wasn't getting fuel and I did have spark. I was probably going to need to get it on the lift to check the fuel pump but a look at the fuel gauge made me think I should try adding fuel to the tank first.

The gas fixed the no-start. It was simply out of gas. There was another problem though. The fuel gauge still showed the same as before.

The customer declined testing for the gauge problem but in my research for testing procedures I had come across a tsb for a calibration procedure that must be done after any repair to "ensure proper operation of the fuel gauge". Now I hadn't done any work on the system but it seemed possible that any intermittent problem, like a poor connection could cause the gauge to need calibration. I did the calibration procedure and the gauge actually did start working. I hadn't found or repaired the problem and I cautioned it could stop working again but I did have a working gauge at the moment.

Thanks for reading!

Kenny@ggauto.repair

2004 Dodge Dakota 4.7 P0335 Code Stored

This truck has a camshaft position sensor and a crankshaft position sensor. Both are similar in design and work in the same manner. Both have three wire terminals. At one terminal each is provided with a five volt supply. At another terminal each is provided with a ground. The other wire is the sensor signal monitored by the PCM (powertrain control module). We consider the 5-volt reference and ground to be inputs to the sensors and the signal to be output.

Notches cut into the tonewheel on the front of the camshaft trigger the output signal to the PCM from the camshaft position sensor. In a similar manner the tonewheel on the crankshaft triggers a crankshaft position sensor signal.

Since the two shafts, cam and crank, need to be correctly timed (synched) the PCM expects to see signals that correspond to that. The PCM compares the signals while the engine is running and even while the engine is cranking on a start.

So. What sets a P0335? The code will set during an engine crank if the PCM doesn't see a crank position signal but has seen at least 8 cam position signals. At first glance that might seem to be a bad crankshaft position sensor but if you give it some thought it could be either sensor. Either one could have an erratic signal and set the code. Or think about this, both sensors could be fine and a wiring problem is causing the code to set. Or the sensors and wiring could be fine and the PCM is either not reading the signal or has its own wiring problem.

POSSIBLE CAUSES 

• Intermittent CMP signal
• Intermittent CKP signal
• (K7) 5 volt supply circuit shorted to voltage
• (K7) 5 volt supply circuit open
• (K7) 5 volt supply circuit shorted to ground
• (K24) CKP signal circuit open
• (K24) CKP signal circuit shorted to voltage
• (K24) CKP signal circuit shorted ground
• (K24) CKP signal circuit shorted to (K7) 5 volt supply circuit
• (K4) sensor ground circuit open
• Crankshaft position sensor
• PCM

Before we get too crazy though keep the simple stuff in mind. While we could use a scope to monitor the signals and try and determine if either sensor signal is bad, or wiring is bad or PCM is bad. We could just swap out the two sensors as a test. Both are pretty much the same design and both are high failure items. The two sensors are relatively inexpensive while diagnostic testing time is not. You would actually save money and time by replacing both sensors with new, clearing the codes and letting the PCM tell you if the problem is still there or not. Yes. Sometimes using a known good part is the better choice. In the case of this particular vehicle the fix was to replace both the cam and crankshaft position sensors.

Thanks for reading!

Kenny
Kenny@ggauto.repair

email me what you would like to see discussed and I'll see if I can find a way!