Fuel Delivery Issue

[solracem]

Hello,

I have a 34' 1989 Fleetwood Bounder on a Chevy P32 Chassis. The darn thing sat for 6 years, so, I've replaced several things. Recently I replaced the carburetor with a Uremco 3-3837 and it's now running. However, it dies going uphill and/or shifting into 3rd and 4th gear.

I was told the throttle position sensor (TPS) and idle air control motor (IAC) should be replaced and it should fix the issue. I was also told that if it does not fix the issue it's most likely because my engine control module (ECM) got use to running a certain way and it probably needs to be replaced as well. The manual says the ECM should be under the steering column support bracket but, it's not there.

I cannot for the life of me figure out where any of those parts are located on my Chevy 454. I've read several threads and see that the TPS is usually on the throttle body (TBI) but, cannot find it. I'm also confused since it has a carburetor and is not fuel injected.

Does anybody know where I can find those components? Or any other suggestions on what could be the problem?

I'm beginning to think that since I do not have a TBI and instead it has a carburetor that I do not have an IAC, or an ECM and the TPS is located in the carb. Am i right?

Also, why does it die? Anybody have any suggestions as to what I should check? It seems as though the fuel filters are getting plenty of gas. So, my thought is that it may be somewhere between the fuel filters and the new mechanical pump.

ANY HELP WOULD BE VERY MUCH APPRECIATED

So far I've replaced these components of the fuel system:
vacuum hoses
carburetor
fuel filters several times
mechanical fuel pump
spark plugs and wires
distributor cap and rotor

Questions Recap:
1. ) Do I have an Idle air control motor, If so, where is it?
2. ) Do I have an engine control module, If so, where is it?
3. ) What can I do to diagnose the fuel delivery issue? Could it be a sensor, a pump, or a filter that I don't know about?

Thanks so much for the help!!

[BrianB]

An engine with a carburetor will not have a TPS, will not have an IAC, and will not have an ECM.


You cannot find those component because they do not exist on your engine.

[cncsparky]

Based on mine and others' experience here, I would start by dropping the fuel tank and checking out the electric fuel pump in the tank.  Likely the hose is split and pump may not be working.  Afterwards, work your way forward, next with the fuel regulator mounted on the chassis near the rear.  Likely see that it is wet, needing rebuild.  Replace old crusty rubber fuel lines from the tank to the mech. pump.

[cncsparky]

http://www.classicwinnebagos.com/forum/index.php/topic,9139.msg50576.html#msg50576

[mambo543]

Hi, I'm working on my complete fuel system , 1989 holiday imperial, p30 . take a deep breath, get under your rig by the front of the fuel tank, You may have an electric primer fuel pump that maybe causing you to have low fuel pressure, due to sitting these pumps fail. I bought mine and wanted to set it on fire because it would do the same thing yours is doing. To do a real test, Fill a 5 gal gas can, put a hose in gas can, connect hose to your fuel pump inlet, and take it for a drive. I put the gas can inside my rig and slid the hose to the fuel pump, If it run right, you are better off to install a new electric fuel pump back by the rear axle frame, It's just a primer pump to push fuel to your engine pump, when you start your engine and the oil pressure build the pump in back shuts off and furl is delivered via a bypass line that is already in place. BTW triple helped me out on my fuel issue, I learned the rest. stay calm while working on it.

[mambo543]

Sorry on the spelling, TribleJ helped me out. What I meant was, when you start your engine
your oil pressure builds up, then your rear pump will turn off.

[M & J]

That's not true mambo453. If the rig has an electric fuel pump in the tank and has the original fuel pump relay, the pump does run for few seconds to prime the system and does shut off. However when the engine starts and oil pressure is sensed, the in tank pump starts running again and continues to run until the engine is shut off.

[mambo543]

ok, but what he stated was that he changed the mechanical pump, That would be on the engine one, so there is one more pump used as a primer pump due to the size of his rig, does that sound right?? I'm going by my rig , maybe

[M & J]

Search for P30 fuel pump on the forums. It would be far better to read what others have said and done instead of me rehashing what is already here. I'm not being rude but there is a wealth of information and guidance on this very subject already posted in other threads.
GM added the in tank pump to prevent vapor lock. It doesn't really prime the system but pressurized it for a quick start.

[mambo543]

I agree with you, How ever, please keep in mind that he is troubleshooting an issue, I'm working and have solved the same, He stated his rig has a carb, not TBI, so I take it to understand his is like mine, We are all here to brain storm issues, I still think he does not have an in tank fuel pump, that is why I was giving my input, by telling him to supply fuel from a gas can to fuel pump and see what happens, I hope you understand just trying to give ideas, When you buy some of these used rigs, lord know what prev owners have done to them without saying anything, That is what I ended up with. God Bless.

[bluebird]

We are here to help, but when you give the wrong info, that's not helping.  89 does have an in the tank pump.

[legomybago]

Yeah 89' has the in tank pump.
The person who stated they had a "pusher" pump installed in front of the fuel tank that shuts off after it receives a signal from the oil pressure sending unit, is a PO installed pump. Someone probably put that external electric pump in the system not knowing they came with one already in the tank from the factory or something? And they were having issues with the fuel system. This is my guess.

[mambo543]

I'm So Sorry , I won't comment anymore, I have a 1989, I dropped my tank to clean and rebuild the sending unit, and changed the hoses, I didn't have in tank pump. Sorry again, Good Day

[legomybago]

I think your 89' chassis would be one of the firsts we've heard of that didn't have an in tank fuel pump? That's all Hm?
We have a few HR owners on this site, maybe they will chime in.

[M & J]

Ya. The very first.

[M & J]

Mambo (and sleeth), reread my original reply. I said IF the coach had an in tank pump, it operates as I described.
The OP doesn't know yet what he has, and my reply describes the function of the in tank pump.
CNSPARKY also echoed an in tank pump. We have yet to see an external pump on a mid 80's and up P30., save for yours now.
But I cannot stress enough for you or the OP to use the search function. The Mighty Oz is specific on using the search before or in addition to posting new threads. Peace out.

[Oz]

But I cannot stress enough for you or the OP to use the search function. The Mighty Oz is specific on using the search before or in addition to posting new threads. Peace out.

This is a very important reinforcement of the reason we have the search and it's value.  This entire topic would already have been answered, or at least the vital info needed to solve it is already available.. IF the search is used. 

In addition, our helpful members who have found this value go the extra mile to help new members by taking the time to use the search and even find the relevant topics and share them in order to resolve the problem as quickly as possible.

So, my question would be, what is the value in disregarding this help and getting into discussions over peace symbols instead? 

And, sometimes advice may be wrong.  It happens.  I've done it myself.  Often, it's simply because we've overlooked   a basic piece of info that would have changed things or even that a PO may have done modifications which we didn't know were mods from the OEM setup simply because it was our first experience with it, so please, don't take correction of the error personally.  Stay focused on the goal of helping.


It's all good.   

[BrianB]

Just as an additional data point - I finished dropping the main fuel tank out of my 86 Chieftain last night. It has an in-tank pump. The fuel line goes to some sort of regulator-looking thing, and then to the 5-hose main/aux selector valve.

[solracem]

All of your responses are great! Thank you so much!

I still have not dropped the tank to see if there is a pump but, I plan to do it this week and will let everyone know if it's there.

End of the day, this RV is going to lead to a ton of family fun but, before we get there there's still quite a bit of learning I need to do. So, being new to this I appreciate everyone who has chimed in and tried to help me.

On a bright note, I've replaced a lot of the fuel system. So, hopefully I've narrowed it down to the tank.

If anyone has suggestions on testing the in tank fuel pump (assuming it has one) before dropping the tank or suggestions on removal without dropping the tank, I would appreciate that as well.

[SLEETH]

if it indeed has a in tank pump=it will have a relay & there is a test wire (green) by the relay for testing the pump circuit=add 12volts & it will pwr up the relay then energize the pump (if  my memory doesn't fail me)im sure some one else will chime in

[M & J]

IIRC, the test lead from the fuel pump relay went to a pin on the ALDL connector used for OBD1 setups. Not having a computer and therefore an ALDL, I don't know if that is an option on this chassis.
One easy way to tell is if you can see the wires coming from the top of the fuel tank, there will be more than 1, or perhaps 2. If it doesn't have an in tank pump. There should also be several hose connections - 3 or 4. 1will get fuel to the engine area, 1 will be a return line, 1 may be for vapor canister and 1 may be for the gennie, unless it's Tee'd outside of the tank. If no pump then there may be only 1 or 2 lines.

[bluebird]

It should still have 3 or 4 lines coming off the top of the tank. If it has an in tank pump it should have a regulator on the frame rail too. That regulator will probably need a new diaphragm and can be bought most any parts place that handles Holley parts.  Make sure you either use the same spring that's in there or the one that's the same color in the kit. Replace all the rubber fuel lines back there also.

[cncsparky]

An interesting observation, if I pull the fuel cap off while the engine is running, I can hear the in tank pump running.

[circleD]

Here's my 2¢ worth. If you want the reliability on the road then plan on rebuilding the regulator if its there in the frame and replace every piece that you can while the tank is down. I even put new bolts and nuts on the tank straps. I know it'll cost more and time consuming but the feeling of reliability is worth it. Myself and others have done this task and its not easy nor fun.
And after you get done, you might have noticed something different on yours than other RVs due to a previous owner  D:oH! . Take pics for reference and you might be able to help someone stranded on the road with your new knowledge. Don't give up and please don't get MAD at others or yourself. It can be done. 

[solracem]

Well everyone, as promised, I believe I've FOUND THE PROBLEM and have loaded some pics.

I'm surprised it even ran actually... 

i?? Anyone have suggestions on how to go about cleaning the gunk and rust out? Or a suggestions on a replacement tank?