View Full Version : Wedge Need Help Badly! - New TR7 Won't Start!

09-18-2004, 06:48 PM
The new baby has problems!
It is a US California Spec injected TR7.

It won't start unless you crank and crank, I got it started once by holding the throttle wide open and cranking the crap out of it, and it ran for a while.

When I let the revs come down to under 1000, it died.

Any ideas? Everything under the hood looks to be in good shape and connected.

I already bought the book on Bosch l-Jetronic injection systems, but it wasn't much help, since it doesn't address the TR7 specifically.

Anyone know of any online guides for troubleshooting the FI TR7?

(I'm a dead man if I don't get it running - I told the wife that it was running, and that was the only way she agreed to letting me buy it - she didn't want another "project" laying around for months.... /ubbthreads/images/graemlins/hammer.gif)


09-18-2004, 08:21 PM
have you checked the timing? that's what my tr7 did one time when the pin on the jackshaft broke. i ended up being 90 degrees off in timing. don't know why it ran.

09-18-2004, 11:35 PM
If you don't have the Bentley manual on TR7s, get it! It has very good troubleshooting procedures for the FI cars.

Although it's not that time of the year (cool/cold weather), you can see if the cold start injector and the thermotine switch are working properly.

Check the air flow meter for proper operation.

Check the fuel flow. If you have the stock electic pump, you should hear a low hum from the back of the car. You can CAREFULLY remove the fuel line from the front of the fuel rail (remember, the system is always supposed to be pressurized), and with the ignition switched on (don't crank), see if you're getting a good flow of fuel. Just remember, be careful...you'll be spraying fuel. Also, the fuel filter.

One more thing, these things tend to confuse you on ignition vs fuel problems. Make sure your coil is good.

09-19-2004, 06:16 AM
check your injectors also. What you need to do is hold your throttle wide open for a full minute, with the power off. Then try starting it. If it starts right up, you have leaking injectors which is causing a flooded situation; making it hard to start. good luck! /ubbthreads/images/graemlins/grouphug.gif im sure with all of us, we will get this figured out /ubbthreads/images/graemlins/smile.gif

09-19-2004, 12:06 PM
I have a cd of classic british car manuals I bought in the UK. Can burn you a copy, but don't know if it has FI data. "PDF" format. Also has TR6 and MGB manuals on disk.

09-19-2004, 03:46 PM
The first thing is to sit down, take a deep breath and plan out sensible steps. Though the problem is likely simple, don't expect some quickie fix by reading this forum.

1) Check for spark. Pull a plug and make sure it looks OK.
2) Check for fuel pressure. Your FI manual has this.
3) Check the timing with a strobe.
4) Pull an injector and check it is firing when you turn things over. Your FI manual has this.

Report back. People will be interested to know if you smell gas while cranking; whether when it runs a bit, it runs on all cylinders or stumbles on a couple.

I'm guessing fuel pump or fuel pressure regulator but you have to get the full picture first.

(yes I do have a TR7 PI /ubbthreads/images/graemlins/smile.gif )

09-19-2004, 08:51 PM
Just a word on cranking the FI engine with the throttle open. This can generate a backfire that can damage the flow meter. The voice of experience here. The L- jetronic book,if it's the one I've in mind is a good one if you take some time with it. The systems are the same on all vehicles. Take time to find the referenced component on your car and it will make sense. The FI 7 is an excellent and reliable one when it's right. Approach it systematically and don't panic. You'll be fine, and the guys on this forum are tops, keep them posted. Check out the threads re: this same thing within the last year. Good Luck!

09-19-2004, 10:02 PM
Hey guys, did anyone read the entire post?

I cranked the crap out of it, and it started and ran for as long as I wanted to hold it around 2000 rpm. It died when I tried to take my foot off the gas.

This would tell me that it is not out of time, that it is getting fuel and spark, but it might be getting flooded by leaking injectors.

I'll try the trick about holding the throttel open with the switch off.

09-19-2004, 11:34 PM
that's what happened when the pin broke on my jackshaft. would run for some reason above 1500 rpm and then die. that's why i suggested checking the timing.

09-19-2004, 11:42 PM
Hey guys, did anyone read the entire post?

I cranked the crap out of it, and it started and ran for as long as I wanted to hold it around 2000 rpm. It died when I tried to take my foot off the gas.

[/ QUOTE ]

Yep, read the whole thing. THe symptoms you're descibing fit my FI TR7 to a "T" when I took it out of storage this past spring. If I left the key on (pressurizing the system), cranked it, and then repeated the process about 4-5 times, flooring it, it would start, but I had to give it gas to keep it going. Once the thing warmed up it would run fine. What I found was a faulty cold start injector (which acts like a choke on a carb'ed car). I replaced it and the connector, and the car has started and ran fine ever since ::knocks on wood:: /ubbthreads/images/graemlins/hammer.gif

However, as you say that the symptoms could be caused by flooding from a leaky injector, they could also be caused by a stuck open air flow meter, which is reporting high air flow, and therefore the ECU is calling for more gas, especially when the motor is cold.

/ubbthreads/images/graemlins/iagree.gif Dale has a lot of experience with these, so as he cautions, be careful if you try starting it with the gas floored. Your wife will probably be VERY unhappy if you blow up a $700 air flow meter.

09-21-2004, 09:55 AM
OK- Here's the status.

Last night after work, I tried the trick with holding the throttle down for one minute before turning the key on and cranking it - did not work.

I tried cranking it 4,5,6,10 times - did not work.

It is getting spark.

I can't really hear the fuel pump running with just the key on, but I have had it running the other day when I cranked it for like a minute.

It honestly sounds and feels like its not getting any fuel when I crank it. \

Even after cranking it, you cannot smell gas at the exhaust pipe.

Maybe fuel pump, fuel filter, or cold start injector?

(Murphy's law of automotive repair states that one should replace the cheap stuff first)

I just can't understand how its not getting gas when I crank it, if I actually had it running for 10 minutes the other day, at revs as high as two and three thousand rpm.

Any more ideas?

(and thanks again for all the input!)

09-21-2004, 03:14 PM
If you're thinking fuel problem, I'd start checking these items:

With the key on, check at the pump and see if there's power. If no, then check a couple items. First, the eays one...the fuses. Second, the inertial switch located on the left fender (kind of buried under the master cylinder and the pressure reduction valve. You can jumper the plug on it and check the pump power again.

If that's OK, then there's the combined relay located behind the glove box.

If you have power and the pump seems to be running, you can disconnect the fuel line from the fuel rail and turn the key on to see if you are getting fuel delivered. If not, either the filter is clogged or the pump is bad. The OE pump has a small screen inside (not replacable) that can clog