Having problems with your 1989 Ford Ranger ?
Eng runs rough when alt hooked up. changed alt and battery turn heater fan on and head lights it runs better I've checked all the grounds I could find.
I would take a look at the fuel pressure to see if the delivery is correct. It wouldn't be a bad idea to have a Tech scan it if nothing shows up there. It would be probably more cost efficient then chasing after the problem by changing parts.
Repair Help & Product Troubleshooting for 1989 Ford Ranger
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