Car has sat for 2 days. Sprayed starter fluid into intakes. Turned ignition on for about one minute before pump(s) stopped. Started on first crank. Pls tell me what that indicates? If I must check the FPR's myself, how do I get access to them? Thx for your advice, Nodoubt.
Starter fluid is magic (just kidding)! Starter fluid "fixes" two problems: 1. fuel starvation (e.g. lack of fuel pressure) 2. fuel flooding So with starter fluid, your 355 starts as soon as you turn your ignition key. How 'bout that! Pretty cool. Considering the symptoms and behavior that you've listed, I'd think that starter fluid was solving problem #1 above for you. Some component is likely leaking fuel pressure. In the diagram below, one of your two Fuel Pressure Regulators is shown as part #4 (the other is mirrored on the other side of your motor). That's the most likely loss of fuel pressure, but keep in mind that your initial startup fuel pressure loss could come from other sources (bad fuel pump, faulty signal from a crank sensor, slow leak in fuel line/tank/injector/fitting/checkvalve, bad relay or signal to fuel pump relay, low battery, etc.). I would humbly suggest replacing both fuel pump relays with new parts, replacing both fuel pump relay fuses just for grins (good or bad), charging your battery, and installing two new Fuel Pressure Regulators (go with the RockAuto.com clone FPRs for trivial money). That route will cost very little time/money, and if that doesn't fix your problem then I'd further suggest having your crank sensors tested and your fuel pumps tested. In the meantime, be kind to your 355 by spraying in a little starter fluid when cold instead of endlessly cranking your poor starter motor to death. Image Unavailable, Please Login
Hey NoDoubt, Thx for detailed diagnosis. I always suspected fuel starvation but places to look. Both fuel pumps tested good pressure (50-53 psi). Since only hard starting when sitting overnight or longer, I can only suspect fuel draining back. And since RH pump new, the LH pump check valve (internal) may be suspect. I already swapped around the 4 identical relays and no change. Yes I do see the FPR's in the diagram and also in my manual but how do I physically get access to check them? What do I have to remove? Lots? Is there any way to check out the FPR's other than pulling off the tubing (which my mechanic claims he di check already). Using starter fluid procedure is not my preferred method to start the F each time! My significant other would be rolling her eyes! BTW, went to rockauto.com but no part avail. for FPR for my 1995 F355.
I've just got a 348, so I have ZERO experience with gaining access to 355 FPRs, sorry. You would seem to have a leak in there somewhere...FPRs or fuel injectors being high on my list of potential culprits, but there are others. There is actually a free **TEST** that you can do; you can remove the two fuel pump relays and install a jumper wire between two terminals to activate them. Left activated for 30 seconds prior to starting the car cold without starter fluid might give some useful information one way or the other (car starts on first crank just fine that way, or car behaves no differently). That test would rule-in/out crank sensors and relay signals, I'd think. ...but...I'd still place my bet on the problem being one or both FPRs. Call it a hunch.
NoDoubt, My hunch is still either the FPR's or the check valve in the left fuel pump. Maybe tomorrow I'll tackle the FPR's since I've done the one HIR bulb replacement. Depends on my mood and what my significant other has to say! I'm not allowed to have a mistress - only a hobby/toy!
No Doubt, Here's another test I did today. Sprayed starter fluid into both intakes and immediately cranked without waiting - Fired right up first short crank without any hesitation??? Any other ideas? I did confirm rockauto.com sells an OEM Bosch pump for $250. How can I really prove a faulty fuel pump? Remember it pressure tested OK.
I don't know that you need a new pump. What a new pump gets you (temporarily) is so much extra initial pressure that a leak in the system is overcome. I'd think that you'd want to find and fix the leak instead of constantly installing new fuel pumps. By the way, you mentioned that your mechanic thought that turning the key to "on" would run the fuel pumps. Doesn't work that way on 355's and 348's. The fuel pumps only pump when the motor is turning faster than 30 rpms (e.g. from the starter). This is a safety feature in case the motor otherwise wants to keep running after a bad accident. You don't want fuel being pumped at high pressure onto a fire! Anyway, you are going to want to find your faulty component. FPRs, check valves, injectors...whatever. Could even be that your crank sensors aren't sending the right signal. So lets do a test: When your car is stone cold...try to start the motor without starter fluid. Just try one time...just to verify that the car doesn't want to start right up (this is important!). OK, car doesn't start up. Verified. Now spray in the starter fluid and start the motor. She starts! Turn the car off after 8 seconds. Wait 4 seconds. Now attempt to start it one time without starter fluid. Tell me the result (starts right up, or didn't start). This will let us rule in or out the crank sensors (I'll explain how/why later if desired).
OK No Doubt. Before reading your latest suggestions, I tried to start this afternoon (sat for 24 hours) in normal manner - turn ignition and crank. would not start. Took 3 cranks. Tomorrow, will follow your suggestion and report back to you. Thx again for all your help as it has been most frustrating.
Here's the test results: First Crank - will not start Sprayed shorts bursts into each intake - started right up Turned off after 8 seconds and waited 4 seconds - Started right up Pls give me your diagnosis and explanation. Much appreciated No Doubt.
I just got this from Spaghetti_jet from the Technical Q&A forum The definitive way to know for sure whether the fpr & check valves are working is to simply connect a fuel pressure guage to each fuel rail. There's no point in guessing when simple and cheap diagnostic tool will tell you the full story. Connect the guages when the car's been standing a while. You can then take readings with ignition at pos II, then during crank, then during warm-up, at temp and then during shut-off. If you watch the pressure guage once the engine's shut-off you'll be able to see immediately if the check-valves are leaking. If you get hold of a hand vacuum pump with guage you'll also be able to test the FPR's properly. The 355 WSM has a table of correct fuel rail pressures for a given applied mm hg at the FPR. The symptoms you describe could be anything from bad compression to a blocked fuel filter to a bad ECT sensor and lots in between. If I were to hazard an 'internet guess' (worthless) I'd say you might have an air leak up-stream of the MAF somewhere, but internet diagnosis is impossible. Start with fuel rail pressure readings and take it from there...
That means that you do not have a crank sensor signal problem. You've isolated the problem to a fuel pressure leak. Your third start was successful because the fuel rails were still pressurized, even though the engine was still cold. It takes most fuel leaks some amount of time to bleed off significant pressure, but this obviously wouldn't happen in a mere 4 seconds. That's not a compression problem or timing problem or anything else...you have a fuel pressure leak. Internet diagnosis is possible. A fuel pressure gauge will tell you the same thing, with the added benefit of telling you if the leak is only on one specific side of your engine (you have an FPR on each side). You can go that route if desired, but in the end you are going to wind up replacing a leaking fuel component somewhere (like one or both FPRs).
Hi No Doubt. One question - could the fuel leak be in the LH fuel pump (original) i.e. faulty check valve rather than one of the FPR's? Thx for your super technical assistance to help me narrow down the problem. I'm documenting it all for future reference for other 355 owners.
It's possible. Any fuel component or line/rail could be your problem (there could theoretically even be more than one leak). Your 355 is obviously somewhat different, but the most common fuel pressure failure on 348s is each FPR, however.
You are correct in that the 'coolant' temp sensor would likely have a 'cold start' responsibility........... .......................... I just answered F355Bob's question without thinking of troubleshooting......
Well, next step is back into the shop for pressure testing. At least the problem has not prevented me from enjoying the sunny day drives. Ferraris are dream machines! Will keep you posted on final results. Thx again, No Doubt.
Hi No Doubt. Here's details of continuing saga. Have not resolved problem yet. A week ago, car sat at my friend's level carport for 6 hrs.from 11AM to 5PM in about 70-72F weather. Had to crank 4 times to start. Took car into the shop last week and pressure gauges connected to top of fuel filter unit. Ran engine for a few minutes- pressure read 50-52 psi both sides. After sitting overnight, car started right up on first crank. Car sat for another 4-5 hours. Started right up on first crank again. He then loaned me the portable fuel pressure gauge to test at home(attached are the test results). Maybe ambient temperature has a bearing on problem? Or maybe ultimate solution is to keep a can of starter fluid on board?? Any further thoughts? Image Unavailable, Please Login
Revised test results. I noticed when ignition turned on first time, fuel pumps are activated but only to 3 psi. Then must crank to activate fuel pumps again. Here's revised data so far as I'm checking RH fuel pressure again but going to wait 24 hours. Image Unavailable, Please Login
The fuel pumps have a check valve built into them to help keep pressure in the lines. I bought two new pumps and they have check valves on the top of the pump and going to replace them for the same reason. I've had the cold start problem for 10 years. Cold start process has been crank for several seconds, turn key off, then back on back and and car starts right up after lines are repressurized.
You can do a search on here and you will find its a very common issue. Not sure there is any known fixes. My car (95 2.7) has done this since I've owned it, and I'm sure it's a lack of adequate fuel pressure due to not enough pump on-time at first start which could probably be fixed with a timer-relay that has a longer on-time. Another potential cause could be fuel pressure leakdown over time after shutdown. Then when you attempt to start, there is some air in those lines that has to be bled out of the injectors before the fuel gets there. Also the engine bay temps on the 355 are extremely high, causing the fuel that's sitting in the rails and piping to get very hot and expand. then on cooldown that fuel no longer displaces the same volume. That in turn can cause cold start fuel starvation. Just my $.02
I've had my 95 for 20 years. The first 10 years it started cold first turn of the engine. Last 10 years its has not. I have two new pumps to install and the tech sheet shows a check valve on the top of each pump. I think that is what has failed over time. We have two pumps vs one for later cars so if one valve goes bad, not enough fuel to fire that bank. I think the FPR regulates pressure. The check valve in the pumps keep fuel in the lines and prevents draining back of fuel.
I had a gremlin in starting my car about 6 to 12 months ago. Replaced fuel pump and all sorts of things. You know what it was in the end!!!!! I put a brand new Ferrari crank reference sensor in and never measured the air gap!!!! Well I took it back out and measured the new one against the old one and low and behold it was shorter. Took the factory shims out put it back in the car so the air gap was at the halfway point. Car has never had a starting problem again. If your sensor has been changed or is a bit crook I'd suggest a new one installed within the WSM specs
I should also add that I didn't take into consideration that your car is a 2.7 version. But I'd still look at those sensors. If it was a check valve issue I'd be surprised because when you hit the key those fuel pumps would fill the and have pressure very quickly!!
