Engine wont go past 30 mph when warm

Please clarify what you mean by "i barely touch the breaks and it trys to stop". It's supposed to stop when you hit the brakes so I'm guessing you mean something unusual is happening. If the car will not creep ahead when idling in gear you may have a constricted front rubber flex hose. The clue is after forcing the car to go a few miles that wheel will be very hot from the brake failing to fully release.

This is unbelievable! We always joke that everything comes in pairs. Two head gaskets in a row. Two bad struts in a row. Two of everything. I had this same problem with my '89 Grand Voyager two years ago after it sat outside all winter, and I just developed this problem today, (well, yesterday), with my daily driver '88 Grand Caravan. In my case the actual fix took less than ten seconds. It took longer to find the needed screwdriver.

I suspect you have the same problem but it will require replacing the rubber flex hose. On mine there is a metal bracket crimped around the middle of the hose. Rust builds up inside that crimp and slowly constricts the hose. It is easy to force brake fluid through that restriction by pushing on the pedal but the fluid can't return to the reservoir when you release the pedal. That makes that brake stay engaged and dragging. To fix mine I just had to twist a large screwdriver in that crimp to open it up a little. The symptoms were very subtle at first. Being a brake system specialist I could sense there was something wrong but it wasn't until it suddenly started having no coasting ability, and was hard to accelerate that I knew what was going on. On the other van two years ago the clue was the pedal was real high and hard because no fluid was going to one wheel. Under light braking. After hard braking which forced the fluid through, it would drag very badly and get real hot.

You can verify this by getting it to drag, then park on a slight incline in neutral, place a block a few inches downhill of one of the tires so you don't look silly chasing after the car when the brake releases, then open the bleeder screw on the caliper of the suspect wheel. If the brake releases that proves brake fluid was trapped. You can also loosen the steel lines at the master cylinder. If that lets the brake release we have to discuss fluid contaminated with a petroleum product. That's a very expensive repair. Lets hope the brake does not release when you loosen the lines at the master cylinder.

Your hoses also have a metal bracket near the middle but those are just stamped tin and aren't stiff enough to cause this problem. What you DO have is six crimped connections instead of the normal two; one on each end. I don't know why they made it so complicated but rust can build up in any one of them.

Cancel that order. The master cylinder CAN cause the brakes to lock up but there's two possibilities here. First of all, if both front brakes are locking up, you will verify the master cylinder is the cause by loosening the steel lines attached to it. If that's where the brake fluid is trapped it's because the seals have swelled and grown past the return ports, blocking them. That is only caused by the fluid being contaminated with a petroleum product such as engine oil, transmission fluid, power steering fluid, or axle grease. That is a real serious problem and repairs would exceed the value of the car. The only proper fix for that is to remove every part in the system that has a rubber part that contacts the brake fluid, flush and dry the steel lines, THEN install all new parts and refill the system. That includes front calipers, rear wheel cylinders, master cylinder, combination valve, and all of the rubber flex hoses. If any single rubber part is not replaced that contamination will leach out of it and recontaminate all the new parts. The additional clue is the rubber bladder seal under the reservoir cap will be blown up and mushy.

My guess is you have only one front brake locking up and that is usually caused by a constricted rubber flex hose as I mentioned previously. When that is restricted the brake will not release when you loosen the lines at the master cylinder, but it will when you open the bleeder screw on the caliper. If that's what happens, you need to replace that hose. Two things cause that restriction. One is the rust buildup in the crimped connectors, and the inner liner can be torn and become a check valve when someone removes the caliper and lets it hang by the hose.