Hot start problem resolved due to failed check valve in the DMCH fuel pump

[cybercusp]

Yes - on the output from the fuel pump to the accumulator.

+1
It should be installed/spliced within the hose that leads to the innermost hard fuel line..the hard line closest to the middle of the car; that should be the sending line from the fuel pump to the engine and the one that will be getting the check valve.

I'm at a week now of driving it daily and still no hot start problems. It fires immediately no matter how long it's been sitting.

[rothsean]

+1
It should be installed/spliced within the hose that leads to the innermost hard fuel line..the hard line closest to the middle of the car; that should be the sending line from the fuel pump to the engine and the one that will be getting the check valve.

I'm at a week now of driving it daily and still no hot start problems. It fires immediately no matter how long it's been sitting.

Me too, I am at 3 weeks and it fires quickly. I installed the $7 black plastic CV.

[refugeefromcalif]

I also added an In-Line Check Valve yesterday.
I have the New DMCH fuel pump combo, and for $399.99 It's cost me more in headaches, (And diagnostic $$$), then my old fuel pump and Inaccurate sender.
It's only been 48 hrs. but, my car starts Any time so far. Hot or Cold. I haven't had access to a fuel pressure gauge though and check Rest Pressure.

Here's a couple pics of my install on the fuel FEED line.





George

[refugeefromcalif]

Question for those with the New fuel pump combo and have added a Check Valve.

How many are Wanting/trying to return their units for replacement? (Hoping for an integrated check valve in the combo that works)..

I'm on the fence on this. Do I mess with something that now Works or, go back to possibile starting problems?

George

[Jimmyvonviggle]

Question for those with the New fuel pump combo and have added a Check Valve.

How many are Wanting/trying to return their units for replacement? (Hoping for an integrated check valve in the combo that works)..

I'm on the fence on this. Do I mess with something that now Works or, go back to possibile starting problems?

George

I think it's easier to just buy the extra check valve than removing it,shipping it back, and waiting for a new one. Of course there are those that will do this to maybe prove a point, and I understand this feeling.

[NightFlyer]

Question for those with the New fuel pump combo and have added a Check Valve.

How many are Wanting/trying to return their units for replacement? (Hoping for an integrated check valve in the combo that works)..

I'm on the fence on this. Do I mess with something that now Works or, go back to possibile starting problems?

George

Not worth it IMHO. I'm all about functionality. The unit works great (or at least appears to thus far) other than the inherently bad internal check valve problem. BTW, the external in-line check valve that I ordered just arrived in the mail today - will be installing it sometime during the next couple days. I just had another hot start problem today, despite DMCH insisting that my unit should have a good/working internal check valve. The worst part about a hot start problem is that they always seem to happen when you have people gawking at the car - it's embarrassing. We'll find out if in fact my problem is the internal check valve on the fuel pump/sender combo unit soon - although I strongly suspect it is, as everything else still checks out 100% after a triple check of the entire fuel system.

The only way that I'd even consider returning the unit under a warranty claim for a replacement is if they were offering the unit without an internal check valve all together, as then I could just rely solely on the external in-line check valve. In fact, I haven't even complained about my current situation to either Midwest (where I purchased the unit) or Houston - it is what it is and the fix is reasonably affordable and easily doable. Like I said before, I'm thankful that Houston is even out there and offering re-designed/re-engineered products such as this, so while I don't expect perfection (as many here seem to do), as long as the product they're selling is at least 90%, I'm cool with it and will be thankful for the support that they provide to the community. After all, what other marque with about 6,500 remaining vehicles, and about 2,000 or less that are actually roadworthy, have the kind of product support and development that we as DeLorean owners enjoy with our vendors? Personally, I can't think of any.

[StainlessBullet]

I've got a brand new DMC fuel pump sitting in a box waiting for the current pump and sender to go bad.

Same here. I was one of the first that bought this combo kit when it came out. Mine is still in the box and never been used too. I was planning to install it on my project car when it got to that point, but now I'm not so sure.

I agree it would be nice if DMCH sent out letters to their customers letting them know about these problems, especially after spending $400+ on something. I didn't know anything about this issue until Josh @ DPI posted about it on facebook.

[thirdmanj]

Same here. I was one of the first that bought this combo kit when it came out. Mine is still in the box and never been used too. I was planning to install it on my project car when it got to that point, but now I'm not so sure.

I agree it would be nice if DMCH sent out letters to their customers letting them know about these problems, especially after spending $400+ on something. I didn't know anything about this issue until Josh @ DPI posted about it on facebook.

Sounds like the problem is easily corrected with a check valve. Perhaps DMCH should send out a complimentary check valve to everyone who purchased one?

[StainlessBullet]

Sounds like the problem is easily corrected with a check valve. Perhaps DMCH should send out a complimentary check valve to everyone who purchased one?

That would work too. I still think at least a letter should be sent out to everyone that could be affected. The people that are not on this forum will have some troubleshooting to do if they start having problems.

[refugeefromcalif]

The worst part about a hot start problem is that they always seem to happen when you have people gawking at the car - it's embarrassing.

+1.
Although my car gave me problems everywhere, it Really bothered me when a crowd was around...

The only way that I'd even consider returning the unit under a warranty claim for a replacement is if they were offering the unit without an internal check valve all.

After all, what other marque with about 6,500 remaining vehicles, and about 2,000 or less that are actually roadworthy, have the kind of product support and development that we as DeLorean owners enjoy with our vendors? Personally, I can't think of any.

It still Amazes me that we have a nice group of venders available for a car that, (Let's face it), wasn't a Big success when it was new. (Compaired to other cars).

I've decided to keep what's working until it doesn't.

George