My 91 Caravan 3.3 (99k mi) is starting to exhibit a hard starting problem. It ususally takes to tries on the starter to get it going. Once it starts, it runs fine. The fuel pump/filter has been changed recently. Could this be an injector problem? Would an injector that's going south produce a fault code?
Several different things can cause extended-crank conditions. One of the most common is system pressure loss after shutdown. There's a check valve in the fuel pump that stops fuel draining back through the pump. Sometimes that check valve fails and allows drainback, but you say your fuel pump is a recent replacement, so that's not likely to be the problem.
A faulty fuel pressure regulator can bleed pressure off and make it difficult to start the engine after sitting.
Faulty fuel injectors can leak fuel into the cylinders and make it *very* difficult to start the engine after sitting due not only to unpressurized system but also cylinder flooding.
Neither of these faults would set any kind of a code, so your first step is a fuel pressure gauge installed on the fuel rail and watched during cranking, during running, and periodically for the 2 or 3 hours following shutdown.
The problem, of course, is not necessarily as described above. Insufficient voltage to the fuel pump or SBEC during cranking will cause an extended-crank hard start condition. This can be due to a marginal battery, high resistance in any of many electrical connections (battery cable, power disconnect, SBEC, etc.), excessive starter current draw, a faulty ignition switch, and a few other causes.
Step-by-step systematic diagnosis, once again, is the way to find and fix this problem.
And there's excellent step-by-step diagnostics guide in the Factory Service Manual. (not chiltons or haynes)
Ted
More then likely its the check valve in the fuel pump letting the fuel drain back to the tank causing no fuel in the rail to the injectors. The simple check would be before starting the engine cycle the key on for 3 seconds then off then on then off, that will cause the fuel pump to energize and supply fuel to the injectors, now start the engine... My guess is that it will start right up each time you try this.
Glenn Beasley Chrysler Tech
I changed a fuel pump and filter on my '96 Sebring CV, and had the exact same problem for about a week afterward. I then filled the tank to the very top, and the problem went away immediately. I think that the fuel system must have had an air pocket in it somewhere. It has been perfect ever since. I know of one other person who suffered the same malady after a fuel pump replacement.
I have the same problem on my 1993 3.3 GV. The fuel pump died last year and I had it replaced. Sometimes it will start fine other times it takes a few tries. I have noticed recently when it does start it acts as if there's excess fuel in the cylinder, because it almost sounds like a backfire. Is it possible 1 or more injectors are leaking, causing the hard start, and when cranking, it's filling the cylinder with fuel and then when it fires you get the 'explosion' from a little too much fuel ? Checked and replaced the relays and they replaced the fuel filter when they replaced the pump. I haven't put a pressure gauge on it yet. Those things are expensive to use 1 or two times.
thanks, nick
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