Fix Of The Week 7/26/19
Fix of The Week
Every week we’re posting our favorite head-scratchers and interesting mechanical issues submitted by our Direct-Hit customers.
For a chance to have something you’ve worked on appear as a Fix of the Week, and win a cool little prize for your shop, all you have to do is post your unique fixes in Direct-Hit. Just look up the vehicle you’re working on, click on Post Fix at the top right, then tell us the problem and what you did to fix it.
This Week’s Winners
On this edition of Fix of The Week: clicking sounds from both a Honda and a Buick, and a bad intercooler in a Mazda.
2009 Honda Accord – Main Street Auto Repair
This vehicle came in with no A/C compressor operation. You could hear the A/C relay clicking loudly and the scan tool A/C switch and clutch PID both said ON. The scanner said A/C system pressure was at 100 psi, but there was no power at the compressor. We manually operated the relay using the scanner and got the same result. We checked continuity on the A/C compressor power line and had continuity—no short to power or ground. The compressor ground was good. I was going to voltage drop the circuit but swapping relays was way easier.
I swapped the relay with starter relay and the problem was solved. I replaced the A/C relay with a new one. The problem must have been that the relay was not holding the amperage load internally to charge the compressor circuit, even though it was clicking loudly.
2007 Buick Lucerne – Schwabe’s Automotive
The customer noted a clicking noise on right turns only, and the tighter the turn, the more prominent the noise. It sounded like a drive axle, so we replaced the passenger axle shaft but the noise was still there. I looked on Identifix and found a similar scenario: Bendix drive loose on start. I jacked up the passenger side of the car with the motor running and found the Bendix hitting the flywheel. I replaced the starter and the noise went away.
2012 Mazda 3 – Dave’s Ultimate Automotive
This vehicle had poor acceleration/no boost. The DTC code was P0299—bad intercooler. With a scan tool, go into live data and monitor the boost pressure; if there is very little or no change while increasing RPMs, there is likely a leak in the system.
While the engine is running increase RPMs enough to spool the turbo and listen for a loud whooshing noise or loud engine intake noise indicating a leak. Under normal conditions, there is very little engine/turbo noise.
Inspect all intake plumbing for cracks or loose clamps and inspect the intercooler, paying extra attention to the lower end where the lower tank crimps to the intercooler core. Confirm turbo, wastegate, and recalculation valves are all functioning properly. We replaced the intercooler (the lower tank separated from the intercooler core had caused a large leak).