Rough Start, Squeaking, & Hesitant in Stop & Go
 

Hey y’all, not sure if this is in the right sub topic but if it’s not please correct me.

Was looking to see others inputs before I say F it and just bring it to Toyota for a general diagnosis but also don’t want to get bothered about buying a set of tires.

So in short, for the past week, car’s been having a rough time starting. Starts on the first go but takes an extra second or two during the crank to light. Things I’ve checked: cleaned intake filter, cleaned MAF sensor, checked battery. All are good now. Once that’s done cars starts up a lot better and runs a lot better too but rough starts are intermittent. Come a day or two later and now there’s a squeaking noise near front left of vehicle under the hood. Not sure if it’s any significance but would like to bring it up. Squeaking happens during normal cruising driving but mostly heard when going from a stop when RPM’s dip on start.

Come to most recent, was at an In-N-Out line so frequent stop and goes and the car hesitates bad. Right when I put the gas down, RPM’s dip and sounds like it’s almost down. Have to put pedal down all the way to even get some action but car is resisting heavy and takes about 10 seconds of constant RPM dipping til I can get it to 2000k and it’ll go. Once moving it’s fine but seems like going was the hard part.

Thoughts? I know online is not a best place for direct answers but would love to hear your guys trouble shooting steps for a problem like this. Thanks in advance and happy holidays!

how did you test the battery? voltage or load test?

squeaking is usually a belt, i would get a cigarette lighter volt meter and monitor voltage while running-- should be around 14v. i'm suspicious your alternator might be going. it could be loading up the belt and causing the squeak. but given the age, it could also just be that the belt needs to be replaced.

Clean your throttle body
Are you e85 or 91?

I reckon ol @soundman98 got er pegged. - :thumbsup:

Apologies for the late reply gents, just now saw all of the reply’s. Thank you to everyone for taking your time.

Quick update on the situation:
Rough starts turned into squeaking in left side of engine bay after self troubleshooting with cleaning the MAF and getting the battery tested (simple test at Autozone to test it under load turned out battery is good and holds charge).
Squeaking turned into rough idles in stop and go traffic and even up to a stutter. Found a bad vacuum leak on the oil catch can, and once fix now has a CEL as of today. Code runs up as P0087 for fuel pressure issue, and after doing some research concluded that, my DW300C is likely going bad and has caused weak fuel pressure to the the high pressure fuel pump which is causing that squeaking that I’m hearing on the driver side engine and on top of the vacuum leak has caused it to stutter in stop and go and also give it some really struggling starts (in warm conditions / perfectly fine in cold starts).

Conclusion so far is to remove / replace fuel pump, and have gotten in contact with my tuner to see if any other discrepancy needs to be attended to. So if anyone else has gotten a similar issue, I hope this mini trouble shooting tree helps.

Further more, some key things I’ve been seeing that has lead up to this that I could of caught before is that my tank goes empty at 1/4 on the huge before the light even comes on. Have starved the engine twice because of that, and came to the conclusion that fuel pump was most likely improperly installed by me in regards to the O-rings. If anyone else has a similar issue or if it’s normal to be going empty at 1/4 of a tank on the DW300C please let me know. Hope this helps some trouble shooters, and I’ll update as I go.

This is a great example of why if you have issues, you need to state what modifications are done to the car. With that said it certainly sounds safe to assume the fuel pump is the cause

Yeah, hopefully that’s the main cause.

Cars boosted running a SBD500X on 91 making 265 @10PSI tuned by Delicious.
Fueling is stock other than DW300C fuel pump.

Still looking for anyone else with the “tank empty at 1/4 Guage mark” but looks to be a rare problem that I’m assuming was done from improper installation with the O-Rings.

The fuel pump and level sending unit are two parts of an assembly inside your fuel tank so I don’t think the fuel pump is causing your fuel level issue. My guess is that your sending unit was either damaged or the float arm was bent during the installation of the new pump.

First question I want to ask is: Did you or someone else install the aftermarket fuel pump. And just so you know, I have the same year car and same aftermarket fuel pump installed and did it myself, and noted that there was a discrepancy in the instructions that went with the new pump.

Second question I want to ask is: Did you end up stacking the O-rings that came with the new pump or did you use the OEM plastic spacer from your OEM pump along with one O-ring?

Last question, which involves the discrepancy that I mentioned above: Did you use the lubricant that came with the new pump to lube the pump O-ring(s)?

Hey brotha, I appreciate the insight! Will I fear I may have also bent the arm, I have ran across another owner on YT that had the same fuel level problem and his was due to a faulty seal from the O-Rings on his own DW65C, so when he replaced it with an OEM unit the problem went away and gauge rises and dropped as normal so it makes me believe the arm should (hopefully) be fine but I will inspect further.

And to answer your questions, yes I did install it myself and when I did, answers across the board at the time were very inconsistent with using a spacer or not so upon my own installation I believe I did use the lube but I ended up using a spacer and 2 O-Rings. Now after doing some research and reviewing with owners that have installed it as of recent months, I’ve found that a lot have been having success with just using the 3 supplied O-Rings! So once my pump comes in I’ll be going that route and will liberally use the lube and update further.

Thanks brotha

No problem. I used the spacer and one O-ring with the lubricant, and was very careful during the install to not bend or jostle the float or sending unit too much as that sending unit seemed pretty flimsy to me. I have had none of the issues that you are describing and it's been about 3 months.

Of course I don't get to drive mine too much and have only had to fill up once since the new pump was installed.

Am curious as to what the final verdict will be after you replace your pump. Keep us posted.

Hey brotha, forgot to update this thread with the end result,

So after multiple tests, it’s safe to say I was definitely the fuel pump that was causing all the issues. Upon removing and replacing the DW pump with an exact replacement, come to find out I actually I lied and didn’t use the spacer as I originally said, and ended up finding 3 O-rings that looked like it got pinched and mutilated. The fuel pump was having a bad seal and sucking in air.

So I made sure to apply a liberal amount of the supplied grease, and after some test, all problems went away. Gas tank finally went below the 1/4 mark for the first time in over a year and even some more once the light came on, squeaking from the HPFP went away, no more lagging and stalling in stop and go traffic, and the strong stench of a bad A/F mixture from the exhaust went away. Starts up like a charm every time now and can hear the beautiful faint noise of a fuel pump running in the background for the warm and fuzzies haha.

So hopefully this helps any with trouble shooting with similar problems and want to thank everyone for the insight!

That's great to hear. Do you think that the DW pump actually failed or should we just chock it up as an installation mistake, i.e. if you reinstalled the DW pump properly, without pinching the O-ring do you think that would also solve the fuel starvation problem?

I’d say it’s safe to re-run that same pump, most definitely a failed installation on my part because that pump was still kicking! Definitely had a lack of a proper seal and ended up sucking air, and explained all the mini problems, most specifically the fuel level problem!

Now that I have the new one in with proper seals, the noise from the exterior is a lot more noticeable.