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Car repaired from flooding - could there be a problem with fuel pump?

My car was submerged till the windshield in a recent flood (one month before) in my city. My car was absolutely perfect until then. I have now gotten the car repaired since then.

I have been testing the car and it seems to be running fine for most part now. I have been driving at low speeds now and the car has been running. However, there are some issues still:

  1. It is taking a bit longer to start the car. I am kind of sure it’s not the battery since I have kept car running in idle for a couple of hours now and should have been charged as of now.

  2. There is a slight discomfort in accelerating the car. I have not driven the car over 40 kph as yet, but I have noticed that the first time I try move the car, I need to accelerate it a bit more than usual

  3. Every time I turn on, there is a short while when the exhaust sprays water - I live in a tropical city and I doubt there is much condensation inside.

One wonderful fellow community member on another forum suggested it could be the fuel pump. I am curious to hear from the members here if you also think the same. Could water flooding cause the fuel pump to malfunction. For what its worth, the mechanics have dried and replaced the filters and spark plugs.

We had a flood in 2013 and my friend’s motorhome was flooded up to the top of the dashboard. The insurance company condemned the vehicle and paid him out.

Are u near the coast? Salt water flooding is worse than fresh water flooding due to salt corrosion.

Absolutely EVERYTHING could be suspect after an event like that… The worst part of a flood vehicle…is the electrical systems and what they will do to you over TIME… I pray you took on a vehicle submerged in strictly FRESH water…because if it was salt…or salty-ish… Run…do not walk away…run.

I’ve rescued and driven for years several flood vehicles…but I am a bit more suited to take on such frivolity than the average bear and I’ve seen my share of problems let me tell you. Nothing I couldn’t handle but keep in mind I did all the repairs and monitoring of systems…if you need a shop to repair this vehicle…it will or COULD BE an ongoing…never ending series of slow failures of just about anything. Of course the more electronic controls…the WORSE it can be…if its a 1970 VW Beetle on the other hand… You could eliminate all possible suspects in an afternoon and have it permanently repaired for life, but methinks we aren’t talking about a VW Bug from the 70’s however.

If you are not a mechanic or very mechanically inclined…this may not be a road you wish to travel. But good luck… the answer to your question of what the problem Could be…with the vehicle up to its eyebrows in water? is ANYTHING.


Yes it could be the fuel pump; along with a few dozen other things.
Considering the depth of the water has anyone considered taking a gasoline sample out of the tank to see if water is present?

There could well be a number of problems that will rear their ugly head up at some point in time.
That includes contaminated wheel bearings, suspension and steering components, brake components, and transmission fluid just to name a few.

In most cases a car that deep in water is declared a total. Keeping it can mean the car will be fine after the bugs are worked out or it may turn into one thing after the other until one gets fed up and dumps it.

Unfortunately, you’re getting solid advice here. Under the circumstances, any number of things could be wrong now and any number of problems will probably crop up over time. If you can get the car running well now, getting rid of it is definitely worth consideration.

Thanks everyone for wonderful advice. Cartalk did not notify me about these responses.

To answer everyone’s questions - I have got the car completely repaired - emptied/dried the tanks, replaced most of the filters and spark plugs, etc. It was a fresh water flooding by the way.

Today, I took the car for a longer drive and at a good speed too. The latest update is this - the car drives wonderfully well like old times. Just that one niggle remains - you know how you turn your key twice (step 1 turns the battery on, and step 2 cranks the car). The step 2 is taking a bit longer - by around 2-3 seconds more.

I have been researching on this and it looks like it’s the fuel-pump pressure (some have advised elsewhere that it is okay as long as the cranking happens within 15 seconds). Mine is just a couple of seconds extra - so I hope this is not a major issue?

The thing is mechanics in my city are so hard to find at the moment and I will have to wait a month or two before I can take the car for a proper servicing. I can live with this problem till then - that is unless this can be a huge money-sink later on.

The Cartalk web site does not notify you have responses.

Offhand, it sounds like you’re describing a loss of residual fuel pressure. The fuel system is designed to maintain pressure while the car is at rest so startups will be instant.

If fuel pressure drops to zero after the car has been sitting for a while then a leak should be suspected. In most cases this is caused by an iffy check valve in the fuel pump which means a pricy pump replacement all because of a BB and ball point pen spring… :smiley:

Water spitting out of the tailpipe could be water in the gas, water in the cat, oil change sea foam gas treatment and a 200 mile interstate drive at 60mph my recommendation.


To answer everyone’s questions - I have got the car completely repaired - emptied/dried
the tanks, replaced most of the filters and spark plugs, etc. It was a fresh water flooding
by the way.

Is there such a thing as a “complete repair” for a submerged vehicle?

You have a confidence in the repairs that I do not have. It’s easy to make a submerged vehicle run again in the near term. The long term is is the real concern.

While fresh water is much better than salt water, you now have moisture sitting in all electrical connections. Over time corrosion takes place - often leading to intermittent electrical problems.

Did the water cause any pitting on bearing surfaces or on your cylinder walls? Time will tell.

Fresh is better than salt water. You may have the bulk of problems licked. But I’d still not let your concerns go.

Your car may be losing fuel pressure while it sits.

Try this: turn the key from Off to Run (not all the way to Start.) That turns on the fuel pump for a couple seconds - you may hear it run. Turn the key back to Off, then Run, then Off another cycle or two. Then turn the key to Start, which will run the starter motor. Does the engine fire right up… or does the starter motor need to crank for as long or even longer than it has been?

Gotta agree with Joe. A submerged car is never “repaired”. As the rust starts to form in all of the electronics, switches and wire connections, problems will be on going. Seats, carpet, door panels all replaced, or is mold just starting to form? Not to mention all of the mechanical systems like the transmission, axles, and rest of the engine. How could you ever justify spending the money to restore a submerged car?

Thank you everyone for your answers. I understand that the issues may be ongoing but I have got some insurance settlement and would want to get it repaired as much as I can with this amount.

Meanwhile, I noticed that my cylinder warning light went up yesterday when I test-drove my car for a few kilometers. I scanned the car and it throws the following issues:

  • crankshaft position sensor A circuit
  • HO2S heater control circuit low
  • Exhaust gas recirculation
  • Intake air temperature circuit high input

My mechanic says these two issues are not related and I will have to replace them all. But I am kind of skeptical since this warning came up only after I drove the car again for a long distance which could probably mean the ruptured pressure pump could somehow influence this.

Any ideas on this? I don’t trust my mechanic at this point though finding another one seems impossible at the moment.

Sorry, but unless this is Rudolph Valentino’s old Isotta Fraschini, there is absolutely no sense in trying to repair a car that’s been submerged up to its windshield. This car will never be right again.

Just wondering why you didn’t take the insurance company payout and put it towards a new (or new-to-you-used) car. Did this mechanic assure you that he could make it run like new, even though the insurance company totaled it? If so, he’s a complete scam artist. I would not put another nickel into this thing. You’d just be throwing good money after bad. Cut your losses and move on.

An ounce of water left in the transmission will eventually find its way to a clutch disc where it will soak in and wait for the transmission to get hot. Once the oil temperature exceeds 212* the water will boil and seperate the friction material from its disc and that will result in a costly repair.

‘’ car repaired from flooding’’ . .apparently not yet.

Another big issue, mostly not addressed when ‘‘repairing’’ flood damage . . is the wire harnesses.
All of those taped up and conduit wrapped harnesses have been impregnated with water and mud.
EVERY set of gang plugs …every one… needs to be unplugged and each wire terminal removed, cleaned, dried and reassembled.
And, of that mud stays in there , short circuiting will occur later , or now, even if you think everything is dry . .I’ll bet you that it’s not . .AND that same residue WILL absorb future moisture.
COULD be you fuel pump issue now !

You want to REPAIR flood damage ?
You need to take everthing apart, just like a full body-off restoration of a 57 TBird.

Submerged computer boxes will not EVER be dry enough from the outside.
If not completely replaced, each would need to be disassembled, cicuit boards removed, cleaned and dried.
Switches too like headlight, turn signal, ignition, heater, a/c , radio, wipers . .all of them . .disassembled, cleaned and dried.

THIS is why they usually total a flooded vehicle.
Though it CAN be done, it’s far too much time to invest.

How long was it under water? 1 day. 1 week? Am curious of your situation. Maybe u drove down a boat ramp? Fell thru the ice? Probably got caught in a low spot under an overpass on the highway. Always seems to go down a dip in the road.

Suggest to solve the crank position sensor problem first. The next two may resolve themselves once the CPS is fixed. Its definitely possible that sensor or its connector getting under water could damage it. I’d suspect a corroded connector first. An intermittent CPS could cause the engine to run poorly and stumble and make it hard to start. My first guess on the last code, the intake air temperature connector probably somehow has come disconnected during the repair, causing that error code. I’ve accidentally forgot to connect that sensor on my Corolla a few times, easy to do. And the check engine light comes on to remind me that I’m not really much of a mechanic … lol … The good thing, that sensor is in the intake air path and is usually easy to find and re-connect. I should know, I’ve done it enough times myself.