Classic Car Electrical Diagnostics

Classic Car Electrical Diagnostics and Rewiring in Maine

Old wiring causes more classic car headaches than almost anything else. Portland Performance tracks down wiring faults, charging problems, dead gauges, ignition trouble and no start conditions on classic cars and trucks, and rewires them when the original harness is past saving.

We work on American muscle cars, classic trucks, European classics and Japanese classics, at our shop at 1830 Lisbon St in Lewiston.

Heated, secure indoor shopHolley dealerProgress log you can printOwners from across New England
Light blue classic Ford Bronco with the hood open for electrical diagnosis at Portland Performance in Lewiston, Maine

Electrical work we do on classics

  • Wiring faults: shorts, opens, melted or brittle wiring, bad grounds and intermittent problems that come and go
  • Rewiring: repairing damaged sections or replacing a tired harness entirely
  • Charging systems: batteries that keep going flat, alternators and generators, voltage regulators
  • Starting: slow cranking, clicking, no crank and hot start problems
  • Ignition: points, electronic ignition, coils and ignition wiring
  • Gauges and lighting: gauges that read wrong or not at all, lights, switches and accessories
  • EFI and accessory wiring: wiring for EFI conversions, fans, fuel pumps and added electronics, done neatly and fused properly

Find the real cause first

Test before replacing

Electrical problems on classics are rarely fixed by throwing parts at them. We trace the circuit and find what is actually wrong, so the fix holds.

Done right for an old car

Repairs are routed, protected and fused so they hold up on the road, and they look right under the hood.

How a classic job works here

  1. Written assessment first. Before any work starts, we look the car over and give you a written mechanical assessment, so you know what it needs before you commit.
  2. Photos and your approval. You get progress photos as the work happens, and we check with you before going past the budget we agreed on.
  3. A progress log you can follow. We keep a running, blog style progress log on your car as each repair gets done, so you are in the loop the whole way. When the job is finished, print a copy to keep with the car's paperwork.
  4. A care plan and a follow up. When the car leaves, you get a maintenance plan covering fluids, cooling, fuel, brakes, tires and seasonal layup, and we follow up after your first few drives.

Questions we hear

My classic keeps draining the battery. Can you find out why?

Yes. We track down battery drains, charging problems and intermittent electrical faults, and we find the cause before replacing anything.

Can you rewire my whole car?

Yes. We repair damaged sections when that makes sense, and replace the harness when the original is past saving.

Do you wire EFI conversions?

Yes. We are a Holley dealer and wire and calibrate Holley and FiTech systems. See Holley EFI tuning and conversions.

Which classics do you work on?

We work on American muscle cars, classic trucks, European classics and Japanese classics. If you are not sure whether your car is a fit, call or send us a message with photos.

Do you do paint or bodywork?

No. We do the mechanical side only, and we are glad to work alongside your paint and body shop. See classic car and truck service for everything we handle.

Where is my car kept while you work on it?

Indoors in our heated, monitored shop at 1830 Lisbon St in Lewiston, from drop off to pickup. Winter classic work comes with discounted storage while the vehicle is here, and major builds store free. See how we keep your classic safe.

Talk to us about your classic

Portland Performance, 1830 Lisbon St, Lewiston, ME 04240. Monday to Friday, 8:00 AM to 12:30 PM and 1:30 PM to 5:00 PM (closed for lunch 12:30 to 1:30).

Request an estimate online any time, call during business hours, or send a message with questions or photos and we will get back to you.