toid Posted February 24, 2014 Share Posted February 24, 2014 I was cruising along under prime conditions... then engine started missing, sputtering, no acceleration. I pulled over. Idle was rough. I shut her off. I cranked her up. idle revved as usual, rough but better. I tried to pull off and sputtered up to 35mph. I just replaced CTS, IAC, air filter, plugs & wires, cap & rotor, cleaned TB, new injectors, and cleaned all ground points / connections on the harness as recommended. Been runnung fine, ran great to and from church this am. Tracked down a ground-based lighting problem (wrong bulb in socket from previous owner). ran great leaving town then WHAM. She tanked. Will crank and run but poorly. Any ideas? I've never had a fuel filter go like that all of the sudden from great to foul, but it's my only thought. It was my next task (ain't had her but a month now... I have a list) thanks, Rev. Toid Link to comment Share on other sites More sharing options...
Blue88Comanche Posted February 24, 2014 Share Posted February 24, 2014 Checked the oil? Mine started running poorly once it got between the add mark and the end of the stick.... Have you checked the fuel pressure? Its possible the pump is going out. Link to comment Share on other sites More sharing options...
toid Posted February 24, 2014 Author Share Posted February 24, 2014 Last guy said he just did a new tank n pump job. And I checked the oil. S'good. I just changed it yesterday Link to comment Share on other sites More sharing options...
toid Posted February 24, 2014 Author Share Posted February 24, 2014 What would be the symptoms of a bad cps? Link to comment Share on other sites More sharing options...
onlyinajeep726 Posted February 24, 2014 Share Posted February 24, 2014 Bad CPS would cause stalling and intermittent starting. Ignition coil heat soak possibly? Mine acted up like this when fuel pump started going out. I know you just said that it was replaced by the PO supposedly, but it could've suck some junk from the bottom of the tank. What engine and tranny do you have? I'm assuming it's a '90 via your signature. Link to comment Share on other sites More sharing options...
cruiser54 Posted February 24, 2014 Share Posted February 24, 2014 A fuel pressure check is in order. Perhaps the PO used an Airtex pump. Link to comment Share on other sites More sharing options...
toid Posted February 24, 2014 Author Share Posted February 24, 2014 Somewhere in my last move I lost FP gauge... will get new one tomorrow n check it. I forgot to mention a fuel odor near back of truck briefly yesterday. I dismissed it because it did not recur. Link to comment Share on other sites More sharing options...
toid Posted February 24, 2014 Author Share Posted February 24, 2014 If regulator is bad pressure will be too low or too high? 1990 4.0 auto. Po replaced tank with pump supposedly. Said it was expensive and aggravating. The reason he decided to sell it. Link to comment Share on other sites More sharing options...
toid Posted February 24, 2014 Author Share Posted February 24, 2014 In retrospect, I do not believe I mentioned the backfiring that occurred alongside the sputtering when throttle was applied. Link to comment Share on other sites More sharing options...
toid Posted February 24, 2014 Author Share Posted February 24, 2014 I found the ballast cracked in half this am. Could be the issue... huh? The FP ballast I keep reading about is in the driver fender well up near the air box, right? Link to comment Share on other sites More sharing options...
cruiser54 Posted February 24, 2014 Share Posted February 24, 2014 yes. Bypass it. Link to comment Share on other sites More sharing options...
onlyinajeep726 Posted February 24, 2014 Share Posted February 24, 2014 Yea, the ballast just quiets down the pump by reducing the current and voltage going to it. Just connect the two orange wires together and all will be good. Link to comment Share on other sites More sharing options...
toid Posted February 24, 2014 Author Share Posted February 24, 2014 I changed the fuel filter and bypassed Ballast. I could hear the pump running when I turn the key but I could not check to see what the pressure was I could not get a fuel pressure gauge today maybe I will be by the parts store tomorrow to rent it since I couldn't find one to buy. I did manage to get it to crank after a lot of pedal coaxing. Butit dies as soon as you give it throttle. I disconnected the TPS and it died but I don't know what that tells me I may have to tow it to the mechanic if my fuel pressure doesn't tell me anything Link to comment Share on other sites More sharing options...
cruiser54 Posted February 24, 2014 Share Posted February 24, 2014 If it's not the fuel pump itself, it could be the hose internally between the pick-up and pump......... Link to comment Share on other sites More sharing options...
toid Posted February 24, 2014 Author Share Posted February 24, 2014 Either way its a replacement for the pump... I'm assuming. I got a Precision brand pump available at Oreily's. Only 70 bucks. But I hate to keep throwing money... what about the regulator? What are the symptoms of it going out? Its a hard start but it idles pretty well if I can get it started by flooring the throttle. But one touch of the throttle is all it takes to kill it. This makes me regret being stupid. Link to comment Share on other sites More sharing options...
cruiser54 Posted February 24, 2014 Share Posted February 24, 2014 Either way its a replacement for the pump... I'm assuming. I got a Precision brand pump available at Oreily's. Only 70 bucks. But I hate to keep throwing money... what about the regulator? What are the symptoms of it going out? Its a hard start but it idles pretty well if I floor the throttle. But one touch of the throttle is all it takes to kill it. This makes me regret being stupid. Ain't the regulator. Fuel volume and pressure are probably the issue. Carter or Bosch pumps are the best. This can be tested. Link to comment Share on other sites More sharing options...
toid Posted February 24, 2014 Author Share Posted February 24, 2014 Just stopped at oreilys n rented a gauge. If its not too much bother... beyond merely testing pressure on the rail what am I looking for? Key on engine off pressure and key on engine cranking, & if I can get it cranked... with engine running..? Hate to be a burden... Link to comment Share on other sites More sharing options...
cruiser54 Posted February 25, 2014 Share Posted February 25, 2014 Well, Reverend, since we're called to carry each other's burdens, here's what you're looking for. 31 PSI at idle and 39 PSI with the vacuum line removed from the fuel pressure regulator. Link to comment Share on other sites More sharing options...
toid Posted February 25, 2014 Author Share Posted February 25, 2014 Thank you. I was thinking there may have been more to it than that. On my old Super coupe it was 3 different pressures to be measured. S'good to have fellows with genuine concern toward helping folks... I'm generally proficient with OBDII BUT I haven't figured out this jeep setup yet. I just hope I can get it to crank son I can check it at idle. What should it read when the pump pressurizes before cranking? Link to comment Share on other sites More sharing options...
toid Posted February 25, 2014 Author Share Posted February 25, 2014 OK. I turn key on, I can hear the pump. No pressure on the gauge. I turn engine over but will not crank and no pressure on the gauge. Needle doesn't even move. The bad thing is I just filled her up so tank is better than 3/4 full. Link to comment Share on other sites More sharing options...
cruiser54 Posted February 25, 2014 Share Posted February 25, 2014 By golly, you've found it!! Link to comment Share on other sites More sharing options...
toid Posted February 25, 2014 Author Share Posted February 25, 2014 Thanks, brudda. I'll remember u n my prayers . Link to comment Share on other sites More sharing options...
cz777 Posted April 17, 2014 Share Posted April 17, 2014 forget the rest, Bosch pumps are the best hands down ...costly but work great http://shop.advanceautoparts.com/p/bosch-electrical-fuel-pump-kit-69302/20770761-P?navigationPath=L1*14932%7CL2*14986%7CL3*15378 i have pull a few of china made crap out for this kit ......look and see if this will work for you Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now