P0403 Diagnostic and Repair Guide for 1997 Dodge Intrepid - EGR System Issues and ABS Light Troubleshooting

After replacing both the EGR valve and solenoid, the P0403 code returned. I traced the wiring and found one wire showed continuity to the fuse box and another to the Powertrain Control Module (PCM), but both were weak under load. Upon disassembling the harness, I discovered that the internal insulation had degraded due to engine heat. I cut the wires just behind the solenoid connector and spliced in new sections. Since then, the P0403 code has not returned, and the vehicle runs smoothly.

My mechanic diagnosed that the EGR valve was completely sealed shut, which explains the persistent check engine light. We also discovered a brand-new multi-function switch (purchased from CarQuest) failed shortly after installation. A separate short circuit occurred in the column—luckily, my mechanic had access to a donor vehicle with a working unit, as replacing it new would have cost over $150. The ABS light remains on, though. When I replaced the tires, the driver-side rear caliper was extremely tight and wouldn’t allow tire rotation. It required resetting after adjustment; however, I suspect deeper issues may exist. While the EGR is now functional again and wipers are working, the persistent ABS warning is becoming increasingly frustrating.

I recommend scanning for ABS fault codes using an OBD2 scanner to identify specific error codes related to the anti-lock braking system. This will help determine whether a mechanical issue like a seized caliper or wiring failure is causing the problem.

Free diagnostic checks are available at places like AutoZone or Checker Auto Parts—could these services scan for P0403 and ABS-related codes? My mechanic charges $25 just for a basic diagnostic, which can be burdensome when I bring the car in for routine oil changes. He’s reliable and offers quality work with a repair guarantee—if something goes wrong due to his service, he’ll fix it at no cost. This makes his pricing reasonable despite being on the higher side.

It's a fair point—while an Actron code reader priced around $400 might seem like a better long-term investment, paying $25 for a skilled mechanic to interpret codes is actually more cost-effective. For example, if the mechanic recommends replacing a hub and bearing at $100 only to find it’s just a broken wire not detectable by a simple code read, would that still make him trustworthy? A $400 scanner isn’t justified unless you're doing frequent diagnostics—$25 for accurate interpretation from someone who actually fixes cars is a solid value. And yes, if the diagnosis leads to a wrong repair, it's important to ensure the technician has real hands-on experience.

That’s a valid point—given that my car has over 160k miles and is a 1997 model (now 12+ years old), it's not surprising the ABS light is on. I’ve noticed glue-based repairs in the lighting system, suggesting previous owners used substandard fixes. I've already replaced several aging parts—such as the alternator, water pump, idler pulley, and right-side tie rod (a common issue in 1997 Intrepids due to lack of modular tie rod ends). My mechanic noted that one component looked nearly new—possibly replaced by a previous owner or at the used car lot. Off-topic: during mid-temperature gauge readings, the oil light turns on. After shutting down and restarting after ~30 minutes, the engine stalls with RPMs hovering between 650–750. I recall helping my father work on an older 1987 Escort where we could adjust idle—this vehicle runs electronically, so there's no manual idle control. Is there any way to safely increase idle RPM by 100–200 RPMs without damaging the engine?

Could a failing caliper be generating an ABS fault code? It’s worth investigating as a potential root cause.

I’m not familiar with ABS coding, but I suspect the driver-side rear caliper may be causing the issue. When new tires were installed, the mechanic tried to manually spin the tire and found it wouldn’t budge—after removing the ceramic brake pads and applying brake lubricant, it moved smoothly for a few weeks. Now, the ABS light comes on intermittently. It sometimes disappears after driving for an hour or two, but often reappears when I restart the car. Occasionally, it stays on even after shutdown and restart. This behavior suggests either a mechanical binding or a wiring fault in the brake system.