88 5.0 problems

[DarkDragon381]

OK by no means am I stupid when it comes to vehicles but this one has me stumped. I have an 88 f150 5.0. I found water in the oil and in the passenger side tail pipe of the exhaust. My first reaction, blown head gasket, I bought the additive now I get no water in the oil or the exhaust. One would think probem solved, but at low rpm the vehicle is hesitant and dies without gas being applied, at hiway speeds or rpms above 1200 the vehicle runs great minus a slight knock down around the crank. If I take the vacuum off of the break booster (giving a vacuum leak) the vehicle runs better? NO hesitation, idle kicks up and it doesnt die. I cant run a long bed ext cab pickup without power breaks. What does this sound like? I disconected and rerouted all of the vacuum, made sure I had no leaks, changed the oil, I put an MSD coil, cap wires and rotor on, changed the spark plugs, timed it, and it also has a new ICM on the distributor. It acts like a compression problem at low RPM but when it gets going it runs great. ANY help would be appreciated.

[bigredneck47240]

try going to www.fordtrucks.com

[wolf9304]

running an additive does help but it still sound s like you have a blown head gasket and your loosing compresion not all head gasket problems have to have water getting into the oil check your compression on all plugs ive had a similar problem on a nissan truck before hopefully u dont have a cracked block

[Torch]

Yes I agree, sounds like you still have a blown head gasket you probably sealed up most of it but a minor undetectable amount of water/oil is still getting pulled in.

Pull all the spark plugs from both sides of the engine and do a compression test. Check your shop manual for what the PSI should be and what the acceptable cylinder to cylinder variance is.