87 5.7 TBI Hard start question
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CF Junior Member
Joined: Jan 2009
Posts: 38
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From: Yuma Az. Born bred and raised to be an offroader
I have recently pulled the engine and cleaned up the engine compartment and engine including replacing the freeze plugs and have a persistent problem with long hard starts with my truck.
It has a new fuel pump a new IAC valve the TBI was cleaned and there are no vaccum leaks of any kind anywhere. There is no leakage of the injectors at all and I have changed every sensor except the Temp sensor on the intake and the MAF sensor. I don't see here where these would cause the problem I am having. Except the Temp sensor.
I just want verification before throwing more money at this thing trying to correct this problem that I have had since I bought the thing 2 years ago.
It takes about 4 to 5 long cranks, about 3 seconds each before the truck will start. After that the truck runs like a champ. Even under WOT the truck doesn't skip a beat. The engine only has about 30K on it doesn't smoke or make a noise except running like it is supposed to. It can sit for about two hours or better and still on the first crank fire right up.
Is this a temp sensor problem or is this a pressure regulator problem? Fuel pressure is confirmed at 55 psi. so I know thats not the problem. Here are a couple of pics to let you know what I am working with. I know the first pic looks bad but it was only mud and a bit of oil on the engine when it was pulled.
this is what I started with.

this is what I ended with along with the persistent problem.

Any help would be much appreciated. I have read that this problem can come from multiple different scenarios but I am at a loss as to what is causing this. I have been searching this site and the interweb but to no avail. Any and all help is appreciated. Thanks guys and gals.
It has a new fuel pump a new IAC valve the TBI was cleaned and there are no vaccum leaks of any kind anywhere. There is no leakage of the injectors at all and I have changed every sensor except the Temp sensor on the intake and the MAF sensor. I don't see here where these would cause the problem I am having. Except the Temp sensor.
I just want verification before throwing more money at this thing trying to correct this problem that I have had since I bought the thing 2 years ago.
It takes about 4 to 5 long cranks, about 3 seconds each before the truck will start. After that the truck runs like a champ. Even under WOT the truck doesn't skip a beat. The engine only has about 30K on it doesn't smoke or make a noise except running like it is supposed to. It can sit for about two hours or better and still on the first crank fire right up.
Is this a temp sensor problem or is this a pressure regulator problem? Fuel pressure is confirmed at 55 psi. so I know thats not the problem. Here are a couple of pics to let you know what I am working with. I know the first pic looks bad but it was only mud and a bit of oil on the engine when it was pulled.
this is what I started with.

this is what I ended with along with the persistent problem.

Any help would be much appreciated. I have read that this problem can come from multiple different scenarios but I am at a loss as to what is causing this. I have been searching this site and the interweb but to no avail. Any and all help is appreciated. Thanks guys and gals.
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