Fault with Fuel Regulator or Fuel Pump

[Xulfiqar]

you cannot test the pump this way, you need a pressure gauge.

[Xulfiqar]

this is not a regular two pipe system, its a single pipe called "deadhead system" the FPR is in the fuel pump jug - its besides the fuel pump itself when you disassemble the jug. Fuel only flows to the rail but not back.

[SER_GTR]

The Z-Gens Don't use Front Return Line.....They Only Use One Side Pressure Line Which Ends Into Fuel Rail....Won't return Back From Rail...

In Early A Series And E Series And Other Engines...It Use To Flow To Fuel Rail And Excess Of It Returns Back To Tank Via Return Line From Fuel Rail....!!

You need to Check Pressure Using Proper Gauge Just before Fuel Rail In Order To Know The Exact Amount Of Pressure You Are Getting......!!

Checking Using Finger Is Not Going To Tell Anything......! Maintained Pressure Is Needed At Fuel Rail During WOT....Maybe Its Where The Pressure Drops....!

[talhawaleed]

Dear Xulifqar and SER_GTR,

Thank you so much for your reply as Information provided was very helpful regarding the return and sending line.

I have looked for fuel pressure gauge with many mechanics but none of them had this basic item. I will have to pay a visit to Toyata’s showrooms work shop which little out of way from home and office location.

Seems like, two basic simple tests will help only such fuel gage pressure test and injector cleaning from a proper facility, if first one passes.

[SER_GTR]

I Wish They Have One......!!! I Really DOUBT It...They May Have But They Never USE (80% Cases)

So Good Luck...Else You Can Always Make One In Almost Limited Budget ....!

[ahsanonline]

You should record a video showing car first start in the morning. Also do note if theres any black/white/blue smoke on first start.

[talhawaleed]

Sorry guys an Update: problem solved as it was a bad fuel and nothing wrong with injectors or fuel pump. Tank was as clean as it would be in brad new car. So consider filling the car with high octane fuel next time if you experience similar problem.

[talhawaleed]

I need to revive this, as problem again came up and it is worst this time. This entire issue is so shitty that mechanics does not have simple diagnostic tool, toyata Motors spent 3 hours with the car and were not able to diagnose the issue. They don’t have proper equipment such as NOID LIGHT, Fuel injector cleaning equipment and all they tested it with pressure gauge and kept it on for 40 seconds and declared that pressure is fine, anyway I was not satisfied and nor I paid them. Later, once took the vehicle to home and opened the injectors and found them dirty and little clogged. I was able to clean it externally which has improved the issue but problem is still there. Tested the resistance on injectors which were all between 17 OHM to 18 OHMs.

[talhawaleed]

I am sorry, our mechanics have very weak diagnostic skills, I would not want to buy new injectors, then new pump, then new fuel filter, then new pressure regulator, then coal canister, vacuum switch valve as every thing cost money and they are making Literally making me do all this.

[Xulfiqar]

it should be tested when the failure happens. Another issue is that toyota being the cheap ba5tards they are have ommitted a fine fuel filter from the design, this makes way for finer particulate to clog the lines. The older models with filters actually trapped the finer particulate which the pump sock could not block.

The fuel pressure should be tested for a longer time and verified that the system holds pressure. a good pump will make pressure in an instant.

[asad1]

i m having the same problem in my corolla 5afe have replaced injectorsand fuel pump assembly problem remains the same
the only thing left is fuel pressure regulator which is located on fuel rail according to me that regulator is malfunctioning it is not maintaining the required pressure of fuel

[talhawaleed]

Visited Nazir Autos earlier in morning and got the injectors serviced and before asked them to diagnose the issue.

1. he disconnected individual injectors and was able to diagnose that one of the injectors was not running. Smart, as I never thought of attacking the problem this way.
2. Immediately he made a direct connection of that injector by removing the CNG wirings and putting the original female clip on the injector. Problem was already solved, I was so surprised as things are simple for someone who actually knows his way around.
3. Anyway he immediately said that CNG Advancer/Emulators are faulty and further I am advised to consult the CNG guy for replacement of CNG Advancer + Emulator.
4. Injectors were serviced on machine, basically what I wanted and expected from only workshop with injector servicing equipment.
5. Fuel pressure was tested on fuel pressure gage and was found to be consistent on 48 PSI.
6. Once vehicle was turned off, pressure dropped to 43 PSI and stayed there for almost 2-3 minutes till the time gauge was not taken off.
7. Later the evening with assistance from my servant and in hands tools such as Sleeves, Heat gun, and plastic molting machine, I went ahead on mission to correct the faulty wiring and diagnose it further if emulator/ Advancer were really faulty or it was just bad wirings.
8. Basically after two hours of diagnosing and after tracing each and every wire, redoing the wirings where it was insulated with tape was redone with sleeves and heat gun. I found out that female clip of third injector of CNG kit which connects with injector was internally damaged.
9. It was replaced with the new one and problem was solved.

Small issues messes up entire thing, where local mechanics make you go through changing each and every dam equipment whereas entire root of problem lies in small broken connection and most of the times these problems occurs because of poor work man ship.

Thanks for every one for your help especially Xulifqar

[abc01]

what was the price of denso fuel pump and fuel filter

Got the new original Denso (Made in Japan), fuel pump installed but guess what problem still intact.

[talhawaleed]

what was the price of denso fuel pump and fuel filter

i dont remember exactly but i think Denso pump was off Rs 3000 and fuel filter fr Rs 2300 Japan.

[akmal199511]

Suddenly after turning off vehicle it did not started for 40 mins and then started again
Same happened after driving for 15 KM.

Dealership first diagnosed no petrol comes to engine but when the technician remove the fuel pump and check it mannualy by connecting with battery terminal it works fine.

After this 3 test runs done no issue again detected.

Any possible fault and its solution
Car: HONDA BRV-S 3600KM driven

[pwuser151158777448]

I got same issue (hard starting and rough idol) with my gli 2012. In morning there no hard starting observed. Issue arrived during intermediate startup during the day. So I visited toyota gt motors and they suggested to change fuel filter. This cost me around 13500 (only fuel filter and not include regulator or pump). The problem seems gone at service center but after some time same issue occured. I again visited toyota gt motors and this time they suggested to change regulator which costs around 18000.
Anyone know the exact price of these genuine parts.

[talhawaleed]

Its not like, the more you will pay, the better your vehicle will perform. Try to buy an aftermarket fuel filter, have it replaced by some outside mechanic. how did Toyota reached the conclusion that your fuel regulator is bad, it's a small device which does not go bad so easily. did they check the fuel pressure with a fuel pressure gauge, i don't think so, they just firing in the air and overall, they have very had diagnostic skills and will make you change each and every engine part without having your issue fixed. It can be anything, maintain a diary and start by servicing
1. Changing Plugs
2. Clean injectors
3. clean throttle body'
4. change the fuel filter and perform a pressure test on your fuel line.
5. Clean Mass Air Flow Sensor (MAF) sensor with PCB cleaner. you can try thig first, it can be dirty or faulty and this can possibly be an issue and fix would be cheap.

[pwuser151158777448]

Fuel filter changed 3 months ago. Toyota guys checked the fuel pressure through pressure gauge. At that time pressure was maintaining in the line. But somehow when i visited yesterday, after checking the line pressure, it was dropping within minutes. I told them that have already changed the fuel filter. They suggested to change regulator. Can not understand whether the issue is with the new filter assembly or with regulator.

[pwuser151158777448]

Only fuel filter assembly ( excluding pump, regulator and gauge) cost me around 14000. Now addtionally i havre to pay 18000 for regulator. Is it justified?

[UAHMAD]

If changing fuel filter is the solution then you may source it from 'Mithu ka Ahata'. On a couple of shops Kabli pieces are lying in piles. Whole assemblies are available in much cheaper rates than 3S.

I think you did the right thing of buying new filter. The pump can however be purchased in good used condition.