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Hard Starting; Lazy Fuel Pump?


Road Ready

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My Seven with the Zetec engine has always been hard to start. It could start on the second or third try or sometimes takes many more tries.

 

My son says maybe the fuel pump. Do any of you guys have any experience with this problem? Getting to the fuel pump is not simple. I'd hate to do that job if it's not really necessary. The returnless fuel system seems pretty dependent on a very responsive fuel pump.

 

What else should I suspect? The car runs great once started.

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I changed out my fuel pump a few years back. I had hard starting issues and my spark plug (#1 I think) farthest from the fuel inlet was showing signs of it running lean. I put in a Deatsch Werks DW200 fuel pump and the install wasn't too bad. I have a SV so the extra room may make its easier than a S3.

 

Disconnect battery, put on jack stands, remove roll bar and trunk floor, disconnect fuel lines, wiring and vent hose. Remove fuel tank strap and remove tank up thru the trunk. I actually found a pinecone in my fuel tank after I opened it up.

 

PS the DW200 is a larger diameter and the plastic housing will need to be opened up. It took me about 3 hrs to remove the pump.

 

Link to my fuel pump thread.

Edited by jlumba81
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Get a hold of a fuel system pressure test set, not expensive to buy, and test system pressure, the fuel regulator should be maintaining between 27 and 34 PSI with the vacuum hose connected to the regulator. With the vacuum hose disconnected you should see 36-42 PSI.

Other things that cause a hard start: dirty MAF, vacuum leak.

Have you ever changed your fuel filter? (although a problem here tends to result in full throttle stumble.

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Depends also on your ECU setup. Especially aftermarket systems without idle air control valve may need a little gas pedal nursing after start and have a bunch of settings that affect starting based on sensor input or time like startup enrichment and advance, coolant enrichment and advance or the low speed maps in general. No matter what I do, my engine with Emerald ECU needs a few seconds after start to settle into a stable idle.

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  • 2 months later...

Citizzzen, I feel your pain, vicariously, of course.

 

My fuel pressure tested good; 35 psi.

 

I'm developing a theory about when in the start process is a good time to give it a little gas.

 

We're in Indian Summer Part IV here. This weekend might be good for a last run this year.

 

Running with the top off seems less attractive when the temperatures are in the 40s.

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The injectors are all hot with 12 volts (usually on a red wire) as soon as the key is turned to start or run. Only when the computer sends a ground on the other wire does an injector fire. So, make sure the ECU has its ground good and tight and connected to battery ground, not just the nearby skin or frame.

 

You should also check to see what your battery voltage is when you crank it over AND with just the key turned to ON. A weak battery will give you all kinds of problems.

 

Tom

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I used the Noid light set again, this time with the battery fully charged.

 

I saw better results, still most flashes weak or intermittent. I did see only one BRIGHT flash, like the ones in the YouTube video that I watched.

 

To start with, I'll be checking ALL connections. Then it's on to checking other stuff.

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