Got a 87 honda prelude si engines hesitates bad on slight load up hill and wont rev past 2000 rpms changed spark plugs and fuel filter and now wont even idle ????
Asked by Nick Jan 15, 2014 at 03:07 AM about the 1987 Honda Prelude 2 Dr Si Coupe
Question type: Maintenance & Repair
so when it was idling it wouldnt go past 2000 rpms without huge hesitation and so
when i changed the plugs no difference in rpms so i changed fuel filter and after that it
wont start.. i have double checked my work for hours and verified fuel was getting to the
rail ( not sure how to verify pressure) and yah not sure whats wrong if someone has
ideas that would be cool to drive it to m garage to fix rather then a tow if anyone can
help please let me know ??
18 Answers
no i actually just bought it like a week ago and with every paycheck I get closer the problem but im gonna put that on a goal list :)
try a new FPR (fuel pressure regulator) they're fairly cheap
Goodwrench707 answered 10 years ago
Check the attached picture, for some suggestions. I took your picture and altered it. Also, you might want to check into some new plug wires, distributor cap, and rotor. It looks like these haven't been changed in awhile. Re-check your firing order (Plug wire connections).
ok i will do that ill message about it tomorrow thanks man
so air filter is in and there is new wires and cap and rotor and i did an oil change and changed all the fuses and in process of new battery with clamp but i cleaned it up and got that clamp on tight with solid connection on positive side . so when i cranked it over with jumper from other honda it still didnt turn over so i was alone i took a vaccum line shot some ether in there and it turned over then died instantly so inducation of no fuel getting to the cylinders .i took out the spark plugs and one was carbon fouled but the others where kinda lean fired lookin so im thinkin when i changed the fuel filter i clogged the injectors thats probably why it wouldnt go past 2000 rpms and have bad hesitation under any load... so what do you guys think maybe am i am right on or anything else i should do ??? oh i havent dont the fuel pressure regulator thing yet but i will later :)
Goodwrench707 answered 10 years ago
If it ran on ether, then you have ignition. It could be low, or no fuel pressure. On 1985-1987 Preludes, the fuel pump is located behind the left rear wheel. Jack up the car, and install jack stands. Remove the left rear wheel. There will be a cover over the fuel pump, remove it. Check the electrical connections. If they are OK, have a friend crank the engine, listen to the pump, if you can't hear it, tap on the fuel pump with a plastic screwdriver handle. If it starts, your fuel pump has pretty much had it. If you still can't hear the pump, check for power at the yellow/black striped wire, at the pump, while cranking. You should get 12v. If you don't, it could be a bad ECM Main Relay, wiring issue, or trouble with the ECM. If you hear the pump run, and the engine dosen't start, a fuel pressure test with a gauge will be needed. Many parts stores also sell "Noid Lights". A light that you plug into the injector connector, to see if the ECM is pulsing the injector, while cranking the engine. Check the following link. It's for a set,... but you might find someone that sells only the one you need. http://www.autozone.com/autozone/accessories/OEM-6-pcs-noid-light-set/_/N-26gh?itemIdentifier=948078_0_0_
Goodwrench707 answered 10 years ago
One more thing,... If you get battery voltage at the pump while cranking the engine, and the pump isn't working, "dead fuel pump".
Goodwrench707 answered 10 years ago
If you need some "free" basic service info., you can get it on Autozone's website, by registering. You will need a service manual, or subscription (alldata.com or other), if you need more detailed diagnostic info. It will save you time and money, in the long run. Not to suggest that you won't find help here, but you sometimes have to wait awhile, for the answers you need.
Goodwrench707 answered 10 years ago
Cargurus, is a good place to draw on experience of techs and others, that have "been there, done that", and found solutions that might not be found in any service manual.
Goodwrench707 answered 10 years ago
I noticed you stated your getting a new battery. Is it dead, and won't hold a charge? Because if it's too far gone, even a jump start may not supply enough voltage to the ECM (Engine Control Module), while cranking the engine. Meaning the fuel pump won't work, the injectors won't work, etc....
Goodwrench707 answered 10 years ago
If the battery was good before you had trouble, leave it connected to the car you're jumping it off, for at lease 15-20 minutes, before you try to start your car. If not,.. putting in a "known good" battery, should be your first step.
well i definatly gona d the fuel pump thing i kinda suspect that to and i use all data a little bit i dont have to much in my budget to suscribe but on the list mainly i was just wondering like you said whos been there done that and actually you gave me all the info i need ( and i love picking brains lol ) so when thats all done and running ill let yo uknow how i fixed it but that you for all the info came n handy :)
mike_vger_1 answered 10 years ago
You could get a low-cost fuel pressure gauge from harbor freight tools to check your fuel pressure; you will need a banjo fitting and a couple of copper fuel fitting washers in order to do this; Check the pressure at the service bolt on the fuel filter. I used a 12x1M banjo from OTC, but you can just as easily pick up an old fuel line from any junk yard for a buck, cut off the end that fits onto the fuel filter and modify that to attach to the FP gauge. Let us know how you make out with the hesitation.
Another question, what is the spec fuel pressure???
mike_vger_1 answered 9 years ago
OK... I know this thread is over a year old, but a newer question is about the FP - so this should cover a few of the other questions... mike_vger_1 This applies to the '86 Prelude 2.0Si 5Speed manual FI engine, and may be the same for all '85-'87 Preludes, but I cannot say for sure because of the different engines (1.6,1.7,1.8 etc.) - Pressure should be tested with engine idling and the vacuum hose to the Pressure Regulator (FPR) disconnected: 36psi(+/- 3), so if it is between 33-39psi, it's good; if not, first check the FP, if FP is OK, and pressure is too high, check for pinched/clogged return hose/pipe, or bad FPR; if FP is too low, then check for clogged Filter, pinched/clogged fuel hose from tank to FP, failed FPR, leakage in fuel line, or pinched/broken/disconnected vacuum hose to FPR. Good Luck - Mike Note: To test FP, get a Pressure gauge, a 12X1M banjo bolt or do as a previous post suggested to make your own. Then look for your Filter - it should be high up on the firewall of the engine bay. Using a 10mm box wrench slightly loosen the drain bolt to allow pressurized fuel to escape slowly - I shouldn't have to say this but I will anyway - keep all sources of flame, sparks etc., includng cellphones away while you are doing this - gasoline is explosively flammable!!! Once pressure has been relieved (Fuel, that is:) ) , use a couple of 17mm or 15mm, I think, to undo one of the hoses - be careful since these are metal and can bend out of shape which will make it a @#I*% to replace. Now you will use the banjo bolt together with your gauge - basically you are replacing the original bolt with the longer 12x1M bolt so that you can piggyback your test equipment into the fuel system so the engine can run with it connected. The 12x1M bolt is long enough so that you can put the existing fuel connector as well as the pressure gauge testing connecter onto it and then bolt it into the fuel filter. Make sure you use correct sized copper or aluminium washers on each side of the fuel and testing connectors on the bolt - leaks are dangerous. Start up the engine and check for leaks. Then check your pressure readings. Good Luck. One thing, that the OP should check, if he still fooling around with that problem, is to check his wires - these are notorious for being a source of misfiring/missing etc. if they are bad, and you will be running around chasing all sorts of red herrings if you don't check them out first!
mike_vger_1 answered 9 years ago
Here is a pic of the longer banjo bolt with the two feed holes, and the smaller one with one hole which is very like the original fuel line bolt that fits into the fuel filter. The longer shaft is so that both, the fuel line and the test banjo fitting can be attached at the same time. Once you see how the fuel line is connected, it will all click into place in your head :) Good Luck